How many genetic ancestors do you have?

Short answer: you get DNA from about 2ⁿ ancestors n generations back, up to 8 generations, then about 68 additional ancestors for each generation after that.

• Background
• Tables, number of ancestors
• Tables, number ancestors you got 1/2ⁿ of your DNA from
• Miscellaneous observations

Other people have done this same analysis, see here. They got similar but slightly different results than I did.

The number of genealogical ancestors you have n generations is 2ⁿ: 2 parents, 4 grandparents, 8 great-grandparents, and so forth. The only way to have fewer is if some of them are the same person. (For example, I have two great-great-great-great grandparents who are also my great-great-great-great-great grandparents by another line.)

The difference between genealogical ancestors and genetic ancestors is that genetic ancestors are the ones that you actually got some DNA from. They're a subset of your genealogical ancestors. Humans have about 3 billion base-pairs of DNA, so that limits the number of genetic ancestors to about 3 billion no matter how far back you go. There are also around 46,000 hotspots (reference Genetic Crossovers Are Predicted Accurately by the Computed Human Recombination Map, figure 6). Hotspots are the places where crossovers usually happen. Each of the 46,000 segments bounded by neighboring hotspots usually has a single line of descent, so you're limited to about 46,000 ancestors.

But I'm interested in something that happens much sooner than that: after about eight generations back, the number of genetic ancestors only increases linearly with the number of generations, while the number of genealogical ancestors keeps increasing exponentially. Once you go back 20 generations, you have only 1300 or so genetic ancestors despite having over a million genealogical ancestors.

The exponential growth up to 8 generations is due to having many independent chromosome pairs. Humans have 23 pairs of chromosomes, and which side of the pair you inherit from is a random choice for each of the chromosomes. You start out with both sides of the pair yourself. For your parents, you got one side of each of the 23 pairs from each parent. Grandparents, that's about one side of 23/2=12 pairs. Great-grandparents, one side of 6 pairs each. Great-great-grandparents, one side of 3 pairs. Eventually you're down to inheriting DNA on just one side of one pair from each ancestor. At that point the exponential growth of ancestors stops.

The linear growth after that is a bit more complicated. The linear growth is due to having a limited number of crossovers per chromosome per generation. Each generation, you don't just get one side of one of your parent's chromosomes. Instead, the parent mixes their pair before splitting it into two. The process is called meiosis. The points where the pairs cross are called crossovers. There's around one or two crossovers per chromosome pair per generation.

Being more precise about crossovers (reference "Genetic Analysis of Variation in Human Meiotic Recombination"). The 23rd chromosome is special, it's the XY chromosome. If you're a male you have XY, if you're female you have XX. The male does not mix the XY, daughters get the X directly and sons get the Y directly. If you're female you have XX, and XX has about as many crossovers as any other chromosome. Other than that, there's always at least one crossover per chromosome per generation (otherwise meiosis doesn't work properly), and sometimes more than one. How many more is proportional to the length of the chromosome (reference Broad-Scale Recombination Patterns Underlying Proper Disjunction in Humans, figure 5). If you're male, you have an average of 26.4 crossovers total when producing sperm, so spread among 22 chromosomes, that's a little over 1 crossover per chromosome. If you're female, it's more like an average of 41.1 crossovers when producing eggs, so given 23 chromosomes total, that's a little under 2 crossovers per chromosome. Each generation each chromosome does these crossovers, and also decides randomly which side of each chromosome pair to give you.

If you're male, you got your Y chromosome from exactly 1 ancestor n generations back. The X chromosome (men have half a pair, women have a whole pair) is also unusual: you're most likely to get it from your mother's father's mother's father's mother etc, but it might have come from your mother's mother's etc. Reference That Unruly X ... Chromosome That Is.

Tables: number of genetic ancestors N generations back

So ... what's that add up to? How many genetic ancestors do you get n generations back? I simulated it, C++ code here, doing the crossovers at random spots, handling XY correctly, and the number of crossovers per generation for males and females correctly too. Other than XY, I treated all chromosomes as the same: same length, same chance of crossover. Instead of starting with 2ⁿ ancestors and trying to derive a person, I started with a person and worked backwards. Any ancestors contributing no DNA can be ignored, because their ancestors will also contribute no DNA, so the time and space complexity of the simulation is linear with the number of genetic ancestors for however many generations back you want to go.

Here's a table of the results, starting with a female:

# generations	# genealogical ancestors	minimum # genetic ancestors (10000 trials)	average # genetic ancestors (10000 trials)	maximum # genetic ancestors (10000 trials)
0	1	1	1	1
1	2	2	2	2
2	4	4	4	4
3	8	8	8	8
4	16	16	16	16
5	32	31	31.9991	32
6	64	61	63.8462	64
7	128	114	123.973	128
8	256	200	220.158	238
9	512	304	342.472	377
10	1024	419	470.809	520
11	2048	529	590.278	656
12	4096	623	696.141	776
13	8192	710	789.701	873
14	16384	784	873.971	966
15	32768	842	951.927	1047
16	65536	905	1026.05	1131
17	131072	966	1097.73	1206
18	262144	1041	1167.94	1273
19	524288	1096	1237.2	1343
20	1048576	1170	1305.95	1429
21	2097152	1243	1374.49	1504
22	4194304	1309	1442.93	1578
23	8388608	1371	1511.09	1653
24	16777216	1441	1579.37	1722
25	33554432	1506	1647.57	1795
26	67108864	1579	1715.61	1868
27	134217728	1649	1783.77	1934
28	268435456	1719	1851.9	2009
29	536870912	1774	1920.1	2075
30	1073741824	1845	1988.06	2141
31	2147483648	1920	2056.22	2207
32	4294967296	1986	2124.48	2284
33	8589934592	2041	2192.53	2346
34	17179869184	2109	2260.73	2416
35	34359738368	2177	2328.9	2480
36	68719476736	2243	2397	2557
37	137438953472	2296	2465.05	2621
38	274877906944	2354	2533.06	2689
39	549755813888	2429	2601.05	2768
40	trillion	2495	2669.14	2838
41	241	2570	2737.27	2901
42	242	2637	2805.46	2977
43	243	2695	2873.61	3064
44	244	2764	2941.74	3140
45	245	2840	3009.91	3210
46	246	2904	3078.06	3266
47	247	2969	3146.25	3336
48	248	3033	3214.34	3414
49	249	3097	3282.52	3481
50	quadrillion	3168	3350.77	3540
51	251	3237	3418.86	3609
52	252	3307	3486.96	3680
53	253	3366	3555.22	3750
54	254	3426	3623.3	3817
55	255	3493	3691.32	3893
56	256	3557	3759.33	3964
57	257	3626	3827.5	4030
58	258	3693	3895.65	4117
59	259	3761	3963.7	4172
60	quintillion	3815	4031.75	4239
61	261	3873	4099.86	4309
62	262	3930	4167.99	4379
63	263	3989	4236.17	4453
64	264	4059	4304.29	4531
65	265	4118	4372.53	4615
66	266	4183	4440.65	4688
67	267	4263	4508.92	4750
68	268	4333	4576.98	4836
69	269	4405	4645.11	4887
70	sextillion	4470	4713.32	4947
71	271	4530	4781.52	5016
72	272	4594	4849.66	5088
73	273	4649	4917.72	5158
74	274	4723	4985.73	5221
75	275	4787	5053.83	5297
76	276	4859	5121.96	5354
77	277	4931	5190.04	5428
78	278	4984	5258.16	5496
79	279	5057	5326.37	5573
80	septillion	5125	5394.43	5644
81	281	5186	5462.63	5715
82	282	5248	5530.86	5788
83	283	5319	5598.93	5856
84	284	5374	5667.01	5933
85	285	5455	5735.06	5991
86	286	5522	5803.28	6066
87	287	5592	5871.32	6148
88	288	5663	5939.43	6209
89	289	5731	6007.63	6277
90	octillion	5800	6075.8	6340
91	291	5852	6143.95	6407
92	292	5938	6212.16	6487
93	293	5992	6280.17	6573
94	294	6059	6348.32	6635
95	295	6133	6416.35	6699
96	296	6194	6484.44	6766
97	297	6262	6552.45	6831
98	298	6327	6620.46	6917
99	299	6388	6688.61	7001
100	nonillion	6444	6756.64	7076

And again, starting with a male:

# generations	# genealogical ancestors	minimum # genetic ancestors (10000 trials)	average # genetic ancestors (10000 trials)	maximum # genetic ancestors (10000 trials)
0	1	1	1	1
1	2	2	2	2
2	4	4	4	4
3	8	8	8	8
4	16	16	16	16
5	32	31	31.9995	32
6	64	60	63.849	64
7	128	115	123.852	128
8	256	201	219.26	237
9	512	305	340.044	376
10	1024	416	466.124	518
11	2048	519	583.348	649
12	4096	619	687.065	754
13	8192	696	778.726	857
14	16384	774	861.355	955
15	32768	844	937.915	1031
16	65536	915	1010.5	1108
17	131072	972	1080.81	1185
18	262144	1038	1149.53	1255
19	524288	1113	1217.49	1332
20	1048576	1182	1285.14	1399
21	2097152	1241	1352.36	1474
22	4194304	1303	1419.49	1540
23	8388608	1362	1486.56	1609
24	16777216	1434	1553.58	1676
25	33554432	1494	1620.54	1759
26	67108864	1544	1687.49	1833
27	134217728	1605	1754.43	1907
28	268435456	1666	1821.31	1976
29	536870912	1738	1888.22	2042
30	1073741824	1803	1955.14	2114
31	2147483648	1870	2022.08	2176
32	4294967296	1926	2088.86	2243
33	8589934592	1994	2155.77	2323
34	17179869184	2059	2222.76	2388
35	34359738368	2112	2289.61	2460
36	68719476736	2180	2356.56	2514
37	137438953472	2234	2423.47	2582
38	274877906944	2299	2490.44	2652
39	549755813888	2366	2557.32	2732
40	trillion	2440	2624.2	2794
41	241	2502	2691.11	2859
42	242	2562	2757.97	2923
43	243	2615	2824.9	2998
44	244	2673	2891.87	3078
45	245	2741	2958.7	3157
46	246	2805	3025.65	3228
47	247	2859	3092.54	3287
48	248	2930	3159.45	3349
49	249	3001	3226.32	3419
50	quadrillion	3070	3293.22	3480
51	251	3154	3360.29	3548
52	252	3212	3427.34	3628
53	253	3273	3494.15	3695
54	254	3351	3560.96	3762
55	255	3417	3627.94	3822
56	256	3488	3694.86	3890
57	257	3558	3761.77	3968
58	258	3621	3828.65	4042
59	259	3693	3895.51	4108
60	quintillion	3754	3962.48	4172
61	261	3824	4029.43	4252
62	262	3885	4096.45	4325
63	263	3950	4163.37	4390
64	264	4011	4230.29	4468
65	265	4072	4297.16	4528
66	266	4144	4363.97	4608
67	267	4197	4430.84	4684
68	268	4265	4497.86	4753
69	269	4322	4564.87	4826
70	sextillion	4388	4631.81	4898
71	271	4449	4698.85	4966
72	272	4511	4765.77	5040
73	273	4582	4832.7	5107
74	274	4641	4899.51	5177
75	275	4709	4966.38	5242
76	276	4764	5033.21	5310
77	277	4826	5100.24	5378
78	278	4898	5167.24	5462
79	279	4964	5234.29	5533
80	septillion	5033	5301.18	5588
81	281	5110	5368.23	5655
82	282	5172	5435.17	5725
83	283	5233	5501.9	5781
84	284	5293	5568.69	5854
85	285	5353	5635.64	5915
86	286	5409	5702.5	5990
87	287	5472	5769.41	6070
88	288	5538	5836.36	6136
89	289	5606	5903.24	6200
90	octillion	5677	5970.15	6267
91	291	5733	6036.99	6339
92	292	5799	6103.84	6413
93	293	5879	6170.62	6488
94	294	5937	6237.54	6577
95	295	5996	6304.47	6647
96	296	6070	6371.33	6712
97	297	6146	6438.37	6773
98	298	6198	6505.34	6840
99	299	6272	6572.28	6912
100	nonillion	6341	6639.22	6966

Tables: number of genetic ancestors you got 2^-n of your DNA from

One practical upshot of this is that those ancestors you do inherit something from, you inherit a lot from. And large stretches of DNA are passed down from generation to generation, those stretches usually aren't finely divided.

How closely related are cousins? It's pretty much a matter of the number of meioses again, except you go up to a pair of ancestors then down again. Siblings shared half their DNA due to inheriting from both parents. The same chart that shows how much DNA your ancestors contirbuted can show how much DNA cousins will shared, just about. There is the difference that the messiness around the common parents adds about one extra generation of splitting without adding one extra generation of diverging.

How many cousins do you have that share 2^-X of your DNA? That cannot be answered by these charts directly: it is strongly influenced by how many children your ancestors had. If someone shared 2^-X of your DNA, what type of cousin are they probably? Again can't tell, it depends on how many children your ancestors had. If they all had 2 children each, say for 2^-9, you take the mean generation of the 9:??? values and that would tell you (somewhere between 2nd cousin and 100th cousin, with 7th cousin once removed most likely).

How many ancestors X generations back gave you closest to 2^-Y of your DNA from (starting from a female):

generation	nth cousins	Y:Z, where Z ancestors gave closest to 2-Y of the DNA
0		0:1
1	siblings	1:2
2		2:4
3	1st cousins	3:7, 4:1
4		3:1, 4:12, 5:2
5	2nd cousins	4:5, 5:19, 6:7, 7:1
6		5:13, 6:30, 7:15, 8:4, 9:1
7	3rd cousins	5:3, 6:29, 7:44, 8:27, 9:12, 10:5, 11:2, 12:1
8		6:14, 7:56, 8:64, 9:42, 10:22, 11:11, 12:6, 13:3, 14:1, 15:1
9	4th cousins	6:5, 7:45, 8:91, 9:83, 10:55, 11:31, 12:16, 13:8, 14:4, 15:2, 16:1, 17:1
10		6:1, 7:30, 8:100, 9:123, 10:94, 11:57, 12:32, 13:17, 14:8, 15:4, 16:2, 17:1, 18:1
11	5th cousins	7:19, 8:97, 9:152, 10:132, 11:87, 12:49, 13:26, 14:14, 15:7, 16:3, 17:2, 18:1
12		7:12, 8:89, 9:171, 10:166, 11:115, 12:68, 13:37, 14:19, 15:10, 16:5, 17:2, 18:1, 19:1
13	6th cousins	7:8, 8:80, 9:183, 10:195, 11:142, 12:85, 13:47, 14:25, 15:12, 16:6, 17:3, 18:2, 19:1
14		7:5, 8:71, 9:190, 10:220, 11:167, 12:103, 13:57, 14:30, 15:15, 16:8, 17:4, 18:2, 19:1
15	7th cousins	7:3, 8:63, 9:194, 10:242, 11:191, 12:120, 13:67, 14:36, 15:18, 16:9, 17:5, 18:2, 19:1, 20:1
16		7:2, 8:55, 9:195, 10:261, 11:214, 12:137, 13:77, 14:41, 15:21, 16:11, 17:5, 18:3, 19:1, 20:1
17	8th cousins	7:2, 8:48, 9:194, 10:279, 11:237, 12:154, 13:88, 14:47, 15:24, 16:12, 17:6, 18:3, 19:2, 20:1
18		7:1, 8:42, 9:191, 10:294, 11:259, 12:172, 13:99, 14:53, 15:27, 16:14, 17:7, 18:4, 19:2, 20:1
19	9th cousins	7:1, 8:37, 9:188, 10:309, 11:281, 12:190, 13:110, 14:60, 15:31, 16:16, 17:8, 18:4, 19:2, 20:1, 21:1
20		7:1, 8:32, 9:183, 10:321, 11:303, 12:208, 13:122, 14:66, 15:34, 16:18, 17:9, 18:4, 19:2, 20:1, 21:1
21	10	8:28, 9:178, 10:333, 11:324, 12:227, 13:134, 14:73, 15:38, 16:19, 17:10, 18:5, 19:2, 20:1, 21:1
22		8:24, 9:172, 10:343, 11:346, 12:246, 13:147, 14:80, 15:42, 16:21, 17:11, 18:5, 19:3, 20:1, 21:1
23	11	8:21, 9:166, 10:352, 11:367, 12:265, 13:160, 14:88, 15:46, 16:23, 17:12, 18:6, 19:3, 20:2, 21:1
24		8:18, 9:159, 10:359, 11:387, 12:285, 13:173, 14:96, 15:50, 16:26, 17:13, 18:7, 19:3, 20:2, 21:1
25	12	8:15, 9:153, 10:366, 11:407, 12:305, 13:187, 14:104, 15:54, 16:28, 17:14, 18:7, 19:4, 20:2, 21:1
26		8:13, 9:146, 10:371, 11:427, 12:326, 13:201, 14:112, 15:59, 16:30, 17:15, 18:8, 19:4, 20:2, 21:1
27	13	8:11, 9:139, 10:375, 11:446, 12:346, 13:216, 14:120, 15:64, 16:33, 17:17, 18:8, 19:4, 20:2, 21:1, 22:1
28		8:9, 9:132, 10:379, 11:465, 12:367, 13:231, 14:129, 15:68, 16:35, 17:18, 18:9, 19:5, 20:2, 21:1, 22:1
29	14	8:8, 9:125, 10:381, 11:484, 12:388, 13:246, 14:139, 15:74, 16:38, 17:19, 18:10, 19:5, 20:2, 21:1, 22:1
30		8:7, 9:118, 10:382, 11:501, 12:409, 13:262, 14:148, 15:79, 16:41, 17:21, 18:10, 19:5, 20:3, 21:1, 22:1
31	15	8:6, 9:112, 10:383, 11:519, 12:430, 13:278, 14:158, 15:84, 16:43, 17:22, 18:11, 19:6, 20:3, 21:1, 22:1
32		8:5, 9:105, 10:382, 11:535, 12:452, 13:294, 14:168, 15:90, 16:46, 17:24, 18:12, 19:6, 20:3, 21:1, 22:1
33	16	8:4, 9:99, 10:382, 11:551, 12:473, 13:310, 14:178, 15:95, 16:49, 17:25, 18:13, 19:6, 20:3, 21:2, 22:1
34		8:4, 9:93, 10:380, 11:567, 12:495, 13:327, 14:188, 15:101, 16:52, 17:27, 18:13, 19:7, 20:3, 21:2, 22:1
35	17	8:3, 9:87, 10:378, 11:581, 12:516, 13:345, 14:199, 15:107, 16:56, 17:28, 18:14, 19:7, 20:4, 21:2, 22:1
36		8:3, 9:82, 10:375, 11:595, 12:537, 13:362, 14:210, 15:113, 16:59, 17:30, 18:15, 19:8, 20:4, 21:2, 22:1
37	18	8:2, 9:77, 10:372, 11:609, 12:559, 13:380, 14:221, 15:120, 16:62, 17:32, 18:16, 19:8, 20:4, 21:2, 22:1, 23:1
38		8:2, 9:72, 10:368, 11:622, 12:580, 13:398, 14:233, 15:126, 16:66, 17:33, 18:17, 19:9, 20:4, 21:2, 22:1, 23:1
39	19	8:2, 9:67, 10:364, 11:634, 12:602, 13:416, 14:245, 15:133, 16:69, 17:35, 18:18, 19:9, 20:5, 21:2, 22:1, 23:1
40		8:1, 9:63, 10:359, 11:646, 12:623, 13:434, 14:257, 15:139, 16:73, 17:37, 18:19, 19:9, 20:5, 21:2, 22:1, 23:1
41	20	8:1, 9:59, 10:354, 11:657, 12:644, 13:453, 14:269, 15:146, 16:76, 17:39, 18:20, 19:10, 20:5, 21:3, 22:1, 23:1
42		8:1, 9:55, 10:349, 11:667, 12:665, 13:472, 14:281, 15:153, 16:80, 17:41, 18:21, 19:10, 20:5, 21:3, 22:1, 23:1
43	21	8:1, 9:51, 10:343, 11:677, 12:686, 13:491, 14:294, 15:161, 16:84, 17:43, 18:22, 19:11, 20:6, 21:3, 22:1, 23:1
44		8:1, 9:48, 10:337, 11:686, 12:707, 13:510, 14:307, 15:168, 16:88, 17:45, 18:23, 19:12, 20:6, 21:3, 22:1, 23:1
45	22	8:1, 9:44, 10:331, 11:694, 12:727, 13:530, 14:320, 15:176, 16:92, 17:47, 18:24, 19:12, 20:6, 21:3, 22:2, 23:1
46		9:41, 10:325, 11:702, 12:748, 13:549, 14:333, 15:183, 16:96, 17:49, 18:25, 19:13, 20:6, 21:3, 22:2, 23:1
47	23	9:38, 10:319, 11:710, 12:768, 13:569, 14:346, 15:191, 16:100, 17:52, 18:26, 19:13, 20:7, 21:3, 22:2, 23:1
48		9:36, 10:312, 11:717, 12:788, 13:589, 14:360, 15:199, 16:105, 17:54, 18:27, 19:14, 20:7, 21:3, 22:2, 23:1
49	24	9:33, 10:306, 11:723, 12:808, 13:609, 14:374, 15:207, 16:109, 17:56, 18:28, 19:14, 20:7, 21:4, 22:2, 23:1
50		9:31, 10:299, 11:729, 12:828, 13:629, 14:388, 15:215, 16:114, 17:58, 18:30, 19:15, 20:8, 21:4, 22:2, 23:1
51	25	9:28, 10:292, 11:734, 12:848, 13:649, 14:402, 15:224, 16:118, 17:61, 18:31, 19:16, 20:8, 21:4, 22:2, 23:1
52		9:26, 10:286, 11:738, 12:867, 13:670, 14:417, 15:232, 16:123, 17:63, 18:32, 19:16, 20:8, 21:4, 22:2, 23:1, 24:1
53	26	9:24, 10:279, 11:743, 12:886, 13:690, 14:432, 15:241, 16:128, 17:66, 18:33, 19:17, 20:8, 21:4, 22:2, 23:1, 24:1
54		9:23, 10:272, 11:746, 12:905, 13:711, 14:446, 15:250, 16:132, 17:68, 18:35, 19:17, 20:9, 21:4, 22:2, 23:1, 24:1
55	27	9:21, 10:265, 11:749, 12:923, 13:732, 14:461, 15:259, 16:137, 17:71, 18:36, 19:18, 20:9, 21:5, 22:2, 23:1, 24:1
56		9:19, 10:259, 11:752, 12:942, 13:752, 14:476, 15:268, 16:142, 17:73, 18:37, 19:19, 20:9, 21:5, 22:2, 23:1, 24:1
57	28	9:18, 10:252, 11:754, 12:960, 13:773, 14:492, 15:277, 16:147, 17:76, 18:39, 19:20, 20:10, 21:5, 22:2, 23:1, 24:1
58		9:17, 10:245, 11:756, 12:977, 13:794, 14:507, 15:287, 16:153, 17:79, 18:40, 19:20, 20:10, 21:5, 22:3, 23:1, 24:1
59	29	9:15, 10:239, 11:757, 12:995, 13:815, 14:523, 15:296, 16:158, 17:81, 18:41, 19:21, 20:11, 21:5, 22:3, 23:1, 24:1
60		9:14, 10:233, 11:758, 12:1012, 13:836, 14:539, 15:306, 16:163, 17:84, 18:43, 19:22, 20:11, 21:5, 22:3, 23:1, 24:1
61	30	9:13, 10:226, 11:759, 12:1029, 13:858, 14:555, 15:316, 16:168, 17:87, 18:44, 19:22, 20:11, 21:6, 22:3, 23:1, 24:1
62		9:12, 10:220, 11:759, 12:1046, 13:879, 14:571, 15:326, 16:174, 17:90, 18:46, 19:23, 20:12, 21:6, 22:3, 23:1, 24:1
63	31	9:11, 10:214, 11:759, 12:1062, 13:900, 14:587, 15:336, 16:180, 17:93, 18:47, 19:24, 20:12, 21:6, 22:3, 23:1, 24:1
64		9:10, 10:207, 11:758, 12:1078, 13:921, 14:604, 15:346, 16:185, 17:96, 18:49, 19:25, 20:12, 21:6, 22:3, 23:2, 24:1
65	32	9:10, 10:201, 11:757, 12:1094, 13:943, 14:620, 15:356, 16:191, 17:99, 18:50, 19:25, 20:13, 21:6, 22:3, 23:2, 24:1
66		9:9, 10:195, 11:756, 12:1109, 13:964, 14:637, 15:367, 16:197, 17:102, 18:52, 19:26, 20:13, 21:7, 22:3, 23:2, 24:1
67	33	9:8, 10:190, 11:754, 12:1125, 13:985, 14:654, 15:377, 16:203, 17:105, 18:53, 19:27, 20:14, 21:7, 22:3, 23:2, 24:1
68		9:8, 10:184, 11:752, 12:1139, 13:1007, 14:671, 15:388, 16:209, 17:108, 18:55, 19:28, 20:14, 21:7, 22:3, 23:2, 24:1
69	34	9:7, 10:178, 11:750, 12:1154, 13:1028, 14:689, 15:399, 16:215, 17:111, 18:57, 19:29, 20:14, 21:7, 22:4, 23:2, 24:1
70		9:6, 10:173, 11:748, 12:1168, 13:1049, 14:706, 15:410, 16:221, 17:115, 18:58, 19:30, 20:15, 21:7, 22:4, 23:2, 24:1
71	35	9:6, 10:168, 11:745, 12:1182, 13:1071, 14:723, 15:421, 16:227, 17:118, 18:60, 19:30, 20:15, 21:8, 22:4, 23:2, 24:1
72		9:5, 10:162, 11:742, 12:1196, 13:1092, 14:741, 15:432, 16:233, 17:121, 18:62, 19:31, 20:16, 21:8, 22:4, 23:2, 24:1
73	36	9:5, 10:157, 11:739, 12:1209, 13:1114, 14:759, 15:443, 16:240, 17:125, 18:63, 19:32, 20:16, 21:8, 22:4, 23:2, 24:1, 25:1
74		9:5, 10:152, 11:735, 12:1222, 13:1135, 14:776, 15:455, 16:246, 17:128, 18:65, 19:33, 20:17, 21:8, 22:4, 23:2, 24:1, 25:1
75	37	9:4, 10:147, 11:731, 12:1234, 13:1156, 14:794, 15:466, 16:253, 17:132, 18:67, 19:34, 20:17, 21:9, 22:4, 23:2, 24:1, 25:1
76		9:4, 10:143, 11:727, 12:1247, 13:1177, 14:812, 15:478, 16:259, 17:135, 18:69, 19:35, 20:18, 21:9, 22:4, 23:2, 24:1, 25:1
77	38	9:4, 10:138, 11:723, 12:1259, 13:1199, 14:830, 15:490, 16:266, 17:139, 18:71, 19:36, 20:18, 21:9, 22:5, 23:2, 24:1, 25:1
78		9:3, 10:134, 11:719, 12:1271, 13:1220, 14:849, 15:502, 16:273, 17:142, 18:73, 19:37, 20:19, 21:9, 22:5, 23:2, 24:1, 25:1
79	39	9:3, 10:129, 11:714, 12:1282, 13:1241, 14:867, 15:514, 16:279, 17:146, 18:74, 19:38, 20:19, 21:9, 22:5, 23:2, 24:1, 25:1
80		9:3, 10:125, 11:710, 12:1294, 13:1262, 14:886, 15:526, 16:286, 17:150, 18:76, 19:39, 20:20, 21:10, 22:5, 23:2, 24:1, 25:1
81	40	9:3, 10:121, 11:705, 12:1304, 13:1283, 14:904, 15:538, 16:293, 17:153, 18:78, 19:40, 20:20, 21:10, 22:5, 23:2, 24:1, 25:1
82		9:2, 10:117, 11:700, 12:1315, 13:1304, 14:923, 15:550, 16:300, 17:157, 18:80, 19:41, 20:21, 21:10, 22:5, 23:3, 24:1, 25:1
83	41	9:2, 10:113, 11:695, 12:1325, 13:1325, 14:942, 15:563, 16:308, 17:161, 18:82, 19:42, 20:21, 21:10, 22:5, 23:3, 24:1, 25:1
84		9:2, 10:109, 11:689, 12:1335, 13:1346, 14:961, 15:575, 16:315, 17:165, 18:84, 19:43, 20:22, 21:11, 22:5, 23:3, 24:1, 25:1
85	42	9:2, 10:105, 11:684, 12:1345, 13:1367, 14:980, 15:588, 16:322, 17:169, 18:86, 19:44, 20:22, 21:11, 22:6, 23:3, 24:1, 25:1
86		9:2, 10:102, 11:678, 12:1354, 13:1387, 14:999, 15:601, 16:329, 17:173, 18:88, 19:45, 20:23, 21:11, 22:6, 23:3, 24:1, 25:1
87	43	9:2, 10:98, 11:673, 12:1363, 13:1408, 14:1018, 15:614, 16:337, 17:177, 18:90, 19:46, 20:23, 21:12, 22:6, 23:3, 24:1, 25:1
88		9:2, 10:95, 11:667, 12:1371, 13:1429, 14:1038, 15:627, 16:344, 17:181, 18:92, 19:47, 20:24, 21:12, 22:6, 23:3, 24:1, 25:1
89	44	9:1, 10:92, 11:661, 12:1380, 13:1449, 14:1057, 15:640, 16:352, 17:185, 18:95, 19:48, 20:24, 21:12, 22:6, 23:3, 24:1, 25:1
90		9:1, 10:88, 11:655, 12:1388, 13:1470, 14:1076, 15:653, 16:360, 17:189, 18:97, 19:49, 20:25, 21:12, 22:6, 23:3, 24:2, 25:1
91	45	9:1, 10:85, 11:649, 12:1396, 13:1490, 14:1096, 15:666, 16:367, 17:193, 18:99, 19:50, 20:25, 21:13, 22:6, 23:3, 24:2, 25:1
92		9:1, 10:82, 11:643, 12:1403, 13:1511, 14:1116, 15:680, 16:375, 17:197, 18:101, 19:51, 20:26, 21:13, 22:6, 23:3, 24:2, 25:1
93	46	9:1, 10:79, 11:637, 12:1411, 13:1531, 14:1135, 15:693, 16:383, 17:201, 18:103, 19:52, 20:26, 21:13, 22:7, 23:3, 24:2, 25:1
94		9:1, 10:77, 11:630, 12:1418, 13:1551, 14:1155, 15:707, 16:391, 17:206, 18:105, 19:53, 20:27, 21:13, 22:7, 23:3, 24:2, 25:1
95	47	9:1, 10:74, 11:624, 12:1425, 13:1571, 14:1175, 15:721, 16:399, 17:210, 18:108, 19:55, 20:28, 21:14, 22:7, 23:3, 24:2, 25:1
96		9:1, 10:71, 11:618, 12:1431, 13:1591, 14:1195, 15:734, 16:407, 17:215, 18:110, 19:56, 20:28, 21:14, 22:7, 23:4, 24:2, 25:1
97	48	9:1, 10:69, 11:611, 12:1437, 13:1610, 14:1215, 15:748, 16:415, 17:219, 18:112, 19:57, 20:29, 21:14, 22:7, 23:4, 24:2, 25:1
98		9:1, 10:66, 11:605, 12:1443, 13:1630, 14:1235, 15:762, 16:423, 17:223, 18:115, 19:58, 20:29, 21:15, 22:7, 23:4, 24:2, 25:1
99	49	9:1, 10:64, 11:598, 12:1449, 13:1650, 14:1255, 15:776, 16:432, 17:228, 18:117, 19:59, 20:30, 21:15, 22:7, 23:4, 24:2, 25:1
100		9:1, 10:62, 11:592, 12:1454, 13:1669, 14:1275, 15:791, 16:440, 17:232, 18:119, 19:60, 20:31, 21:15, 22:8, 23:4, 24:2, 25:1

For males, the constant 6:1 is from one ancestor contributing 1/46th of the DNA, namely the Y chromosome along the direct paternal line. There are a few strongly related individuals for females too, due to X having crossovers about every other generation.

How many ancestors X generations gave closest to 2^-Y of your DNA from (starting from a male):

generation	nth cousins	Y:Z, where Z ancestors gave closest to 2-Y of the DNA
0		0:1
1	siblings	1:2
2		2:4
3	1st cousins	3:7, 4:1
4		3:1, 4:12, 5:2
5	2nd cousins	4:5, 5:19, 6:7, 7:1
6		5:13, 6:29, 7:15, 8:4, 9:1
7	3rd cousins	5:3, 6:28, 7:44, 8:27, 9:12, 10:5, 11:2, 12:1, 13:1
8		5:1, 6:13, 7:55, 8:63, 9:42, 10:22, 11:11, 12:6, 13:3, 14:1, 15:1
9	4th cousins	5:1, 6:5, 7:44, 8:90, 9:83, 10:54, 11:31, 12:16, 13:8, 14:4, 15:2, 16:1, 17:1
10		6:2, 7:29, 8:98, 9:121, 10:93, 11:57, 12:32, 13:17, 14:8, 15:4, 16:2, 17:1, 18:1
11	5th cousins	6:1, 7:18, 8:95, 9:150, 10:130, 11:86, 12:49, 13:26, 14:13, 15:7, 16:3, 17:2, 18:1
12		6:1, 7:11, 8:87, 9:168, 10:164, 11:114, 12:67, 13:36, 14:19, 15:10, 16:5, 17:2, 18:1, 19:1
13	6th cousins	6:1, 7:7, 8:78, 9:180, 10:192, 11:140, 12:85, 13:46, 14:24, 15:12, 16:6, 17:3, 18:2, 19:1
14		6:1, 7:5, 8:69, 9:187, 10:217, 11:165, 12:102, 13:56, 14:30, 15:15, 16:8, 17:4, 18:2, 19:1
15	7th cousins	6:1, 7:3, 8:61, 9:190, 10:238, 11:188, 12:119, 13:66, 14:35, 15:18, 16:9, 17:5, 18:2, 19:1, 20:1
16		6:1, 7:2, 8:53, 9:191, 10:257, 11:211, 12:136, 13:77, 14:41, 15:21, 16:11, 17:5, 18:3, 19:1, 20:1
17	8th cousins	6:1, 7:1, 8:47, 9:190, 10:274, 11:233, 12:153, 13:87, 14:46, 15:24, 16:12, 17:6, 18:3, 19:2, 20:1
18		6:1, 7:1, 8:41, 9:187, 10:289, 11:255, 12:170, 13:98, 14:52, 15:27, 16:14, 17:7, 18:3, 19:2, 20:1
19	9th cousins	6:1, 7:1, 8:35, 9:184, 10:303, 11:276, 12:188, 13:109, 14:59, 15:30, 16:16, 17:8, 18:4, 19:2, 20:1, 21:1
20		6:1, 8:31, 9:179, 10:316, 11:298, 12:206, 13:121, 14:65, 15:34, 16:17, 17:9, 18:4, 19:2, 20:1, 21:1
21	10	6:1, 8:27, 9:174, 10:327, 11:319, 12:224, 13:133, 14:72, 15:38, 16:19, 17:10, 18:5, 19:2, 20:1, 21:1
22		6:1, 8:23, 9:168, 10:336, 11:340, 12:243, 13:145, 14:79, 15:41, 16:21, 17:11, 18:5, 19:3, 20:1, 21:1
23	11	6:1, 8:20, 9:162, 10:345, 11:360, 12:262, 13:158, 14:86, 15:45, 16:23, 17:12, 18:6, 19:3, 20:1, 21:1
24		6:1, 8:17, 9:156, 10:352, 11:381, 12:281, 13:171, 14:94, 15:49, 16:25, 17:13, 18:6, 19:3, 20:2, 21:1
25	12	6:1, 8:14, 9:149, 10:359, 11:400, 12:301, 13:185, 14:102, 15:54, 16:28, 17:14, 18:7, 19:4, 20:2, 21:1
26		6:1, 8:12, 9:142, 10:364, 11:420, 12:321, 13:199, 14:110, 15:58, 16:30, 17:15, 18:8, 19:4, 20:2, 21:1
27	13	6:1, 8:11, 9:135, 10:368, 11:439, 12:341, 13:213, 14:119, 15:63, 16:32, 17:16, 18:8, 19:4, 20:2, 21:1, 22:1
28		6:1, 8:9, 9:128, 10:371, 11:457, 12:362, 13:228, 14:128, 15:68, 16:35, 17:18, 18:9, 19:4, 20:2, 21:1, 22:1
29	14	6:1, 8:8, 9:122, 10:373, 11:475, 12:383, 13:243, 14:137, 15:73, 16:37, 17:19, 18:10, 19:5, 20:2, 21:1, 22:1
30		6:1, 8:6, 9:115, 10:374, 11:492, 12:403, 13:258, 14:146, 15:78, 16:40, 17:20, 18:10, 19:5, 20:3, 21:1, 22:1
31	15	6:1, 8:5, 9:108, 10:375, 11:509, 12:424, 13:274, 14:156, 15:83, 16:43, 17:22, 18:11, 19:5, 20:3, 21:1, 22:1
32		6:1, 8:5, 9:102, 10:375, 11:525, 12:445, 13:290, 14:166, 15:88, 16:46, 17:23, 18:12, 19:6, 20:3, 21:1, 22:1
33	16	6:1, 8:4, 9:96, 10:373, 11:541, 12:466, 13:306, 14:176, 15:94, 16:49, 17:25, 18:12, 19:6, 20:3, 21:2, 22:1
34		6:1, 8:3, 9:90, 10:372, 11:556, 12:487, 13:323, 14:186, 15:100, 16:52, 17:26, 18:13, 19:7, 20:3, 21:2, 22:1
35	17	6:1, 8:3, 9:85, 10:370, 11:570, 12:508, 13:340, 14:197, 15:106, 16:55, 17:28, 18:14, 19:7, 20:4, 21:2, 22:1
36		6:1, 8:2, 9:79, 10:367, 11:584, 12:529, 13:357, 14:207, 15:112, 16:58, 17:30, 18:15, 19:7, 20:4, 21:2, 22:1
37	18	6:1, 8:2, 9:74, 10:363, 11:597, 12:550, 13:374, 14:218, 15:118, 16:61, 17:31, 18:16, 19:8, 20:4, 21:2, 22:1
38		6:1, 8:2, 9:70, 10:360, 11:610, 12:571, 13:392, 14:230, 15:124, 16:65, 17:33, 18:17, 19:8, 20:4, 21:2, 22:1, 23:1
39	19	6:1, 8:1, 9:65, 10:355, 11:622, 12:592, 13:410, 14:241, 15:131, 16:68, 17:35, 18:18, 19:9, 20:4, 21:2, 22:1, 23:1
40		6:1, 8:1, 9:61, 10:351, 11:633, 12:613, 13:428, 14:253, 15:138, 16:72, 17:37, 18:18, 19:9, 20:5, 21:2, 22:1, 23:1
41	20	6:1, 8:1, 9:57, 10:346, 11:644, 12:634, 13:446, 14:265, 15:144, 16:75, 17:39, 18:19, 19:10, 20:5, 21:2, 22:1, 23:1
42		6:1, 8:1, 9:53, 10:340, 11:654, 12:655, 13:465, 14:277, 15:151, 16:79, 17:40, 18:20, 19:10, 20:5, 21:3, 22:1, 23:1
43	21	6:1, 8:1, 9:49, 10:335, 11:664, 12:675, 13:484, 14:290, 15:159, 16:83, 17:42, 18:21, 19:11, 20:5, 21:3, 22:1, 23:1
44		6:1, 8:1, 9:46, 10:329, 11:672, 12:695, 13:503, 14:303, 15:166, 16:87, 17:44, 18:22, 19:11, 20:6, 21:3, 22:1, 23:1
45	22	6:1, 9:42, 10:323, 11:681, 12:716, 13:522, 14:315, 15:173, 16:91, 17:46, 18:23, 19:12, 20:6, 21:3, 22:1, 23:1
46		6:1, 9:39, 10:317, 11:688, 12:736, 13:541, 14:328, 15:181, 16:95, 17:49, 18:25, 19:12, 20:6, 21:3, 22:2, 23:1
47	23	6:1, 9:37, 10:311, 11:696, 12:756, 13:560, 14:342, 15:189, 16:99, 17:51, 18:26, 19:13, 20:6, 21:3, 22:2, 23:1
48		6:1, 9:34, 10:304, 11:702, 12:775, 13:580, 14:355, 15:197, 16:103, 17:53, 18:27, 19:13, 20:7, 21:3, 22:2, 23:1
49	24	6:1, 9:32, 10:298, 11:708, 12:795, 13:600, 14:369, 15:205, 16:108, 17:55, 18:28, 19:14, 20:7, 21:4, 22:2, 23:1
50		6:1, 9:29, 10:291, 11:714, 12:814, 13:619, 14:383, 15:213, 16:112, 17:58, 18:29, 19:15, 20:7, 21:4, 22:2, 23:1
51	25	6:1, 9:27, 10:285, 11:719, 12:834, 13:639, 14:397, 15:221, 16:117, 17:60, 18:30, 19:15, 20:8, 21:4, 22:2, 23:1
52		6:1, 9:25, 10:278, 11:723, 12:852, 13:659, 14:411, 15:230, 16:121, 17:62, 18:32, 19:16, 20:8, 21:4, 22:2, 23:1
53	26	6:1, 9:23, 10:272, 11:727, 12:871, 13:679, 14:425, 15:238, 16:126, 17:65, 18:33, 19:16, 20:8, 21:4, 22:2, 23:1, 24:1
54		6:1, 9:22, 10:265, 11:731, 12:889, 13:700, 14:440, 15:247, 16:131, 17:67, 18:34, 19:17, 20:9, 21:4, 22:2, 23:1, 24:1
55	27	6:1, 9:20, 10:258, 11:734, 12:908, 13:720, 14:455, 15:256, 16:136, 17:70, 18:35, 19:18, 20:9, 21:4, 22:2, 23:1, 24:1
56		6:1, 9:18, 10:252, 11:736, 12:926, 13:741, 14:470, 15:265, 16:141, 17:72, 18:37, 19:18, 20:9, 21:5, 22:2, 23:1, 24:1
57	28	6:1, 9:17, 10:245, 11:738, 12:943, 13:761, 14:485, 15:274, 16:145, 17:75, 18:38, 19:19, 20:10, 21:5, 22:2, 23:1, 24:1
58		6:1, 9:16, 10:239, 11:740, 12:961, 13:782, 14:500, 15:283, 16:151, 17:78, 18:39, 19:20, 20:10, 21:5, 22:3, 23:1, 24:1
59	29	6:1, 9:15, 10:232, 11:741, 12:978, 13:803, 14:516, 15:292, 16:156, 17:80, 18:41, 19:20, 20:10, 21:5, 22:3, 23:1, 24:1
60		6:1, 9:13, 10:226, 11:742, 12:994, 13:823, 14:531, 15:302, 16:161, 17:83, 18:42, 19:21, 20:11, 21:5, 22:3, 23:1, 24:1
61	30	6:1, 9:12, 10:220, 11:743, 12:1011, 13:844, 14:547, 15:312, 16:166, 17:86, 18:44, 19:22, 20:11, 21:6, 22:3, 23:1, 24:1
62		6:1, 9:11, 10:214, 11:743, 12:1027, 13:865, 14:563, 15:321, 16:172, 17:89, 18:45, 19:23, 20:11, 21:6, 22:3, 23:1, 24:1
63	31	6:1, 9:11, 10:207, 11:742, 12:1043, 13:886, 14:579, 15:331, 16:177, 17:92, 18:47, 19:23, 20:12, 21:6, 22:3, 23:2, 24:1
64		6:1, 9:10, 10:201, 11:742, 12:1059, 13:906, 14:595, 15:341, 16:183, 17:95, 18:48, 19:24, 20:12, 21:6, 22:3, 23:2, 24:1
65	32	6:1, 9:9, 10:196, 11:741, 12:1075, 13:927, 14:612, 15:351, 16:188, 17:98, 18:50, 19:25, 20:13, 21:6, 22:3, 23:2, 24:1
66		6:1, 9:8, 10:190, 11:739, 12:1090, 13:948, 14:628, 15:362, 16:194, 17:101, 18:51, 19:26, 20:13, 21:6, 22:3, 23:2, 24:1
67	33	6:1, 9:8, 10:184, 11:738, 12:1104, 13:969, 14:645, 15:372, 16:200, 17:104, 18:53, 19:27, 20:13, 21:7, 22:3, 23:2, 24:1
68		6:1, 9:7, 10:178, 11:736, 12:1119, 13:990, 14:662, 15:383, 16:206, 17:107, 18:54, 19:27, 20:14, 21:7, 22:3, 23:2, 24:1
69	34	6:1, 9:7, 10:173, 11:734, 12:1133, 13:1011, 14:679, 15:393, 16:212, 17:110, 18:56, 19:28, 20:14, 21:7, 22:4, 23:2, 24:1
70		6:1, 9:6, 10:168, 11:731, 12:1147, 13:1032, 14:696, 15:404, 16:218, 17:113, 18:58, 19:29, 20:15, 21:7, 22:4, 23:2, 24:1
71	35	6:1, 9:6, 10:162, 11:728, 12:1161, 13:1053, 14:713, 15:415, 16:224, 17:116, 18:59, 19:30, 20:15, 21:8, 22:4, 23:2, 24:1
72		6:1, 9:5, 10:157, 11:725, 12:1174, 13:1074, 14:730, 15:426, 16:230, 17:120, 18:61, 19:31, 20:15, 21:8, 22:4, 23:2, 24:1
73	36	6:1, 9:5, 10:152, 11:722, 12:1187, 13:1095, 14:748, 15:437, 16:236, 17:123, 18:63, 19:32, 20:16, 21:8, 22:4, 23:2, 24:1, 25:1
74		6:1, 9:4, 10:147, 11:719, 12:1200, 13:1116, 14:765, 15:448, 16:243, 17:126, 18:64, 19:33, 20:16, 21:8, 22:4, 23:2, 24:1, 25:1
75	37	6:1, 9:4, 10:143, 11:715, 12:1212, 13:1137, 14:783, 15:460, 16:249, 17:130, 18:66, 19:33, 20:17, 21:8, 22:4, 23:2, 24:1, 25:1
76		6:1, 9:4, 10:138, 11:711, 12:1224, 13:1158, 14:801, 15:471, 16:256, 17:133, 18:68, 19:34, 20:17, 21:9, 22:4, 23:2, 24:1, 25:1
77	38	6:1, 9:3, 10:133, 11:707, 12:1236, 13:1179, 14:819, 15:483, 16:262, 17:137, 18:70, 19:35, 20:18, 21:9, 22:4, 23:2, 24:1, 25:1
78		6:1, 9:3, 10:129, 11:703, 12:1247, 13:1200, 14:837, 15:494, 16:269, 17:140, 18:72, 19:36, 20:18, 21:9, 22:5, 23:2, 24:1, 25:1
79	39	6:1, 9:3, 10:125, 11:698, 12:1258, 13:1221, 14:855, 15:506, 16:276, 17:144, 18:73, 19:37, 20:19, 21:9, 22:5, 23:2, 24:1, 25:1
80		6:1, 9:3, 10:121, 11:694, 12:1269, 13:1241, 14:873, 15:518, 16:282, 17:147, 18:75, 19:38, 20:19, 21:10, 22:5, 23:2, 24:1, 25:1
81	40	6:1, 9:2, 10:116, 11:689, 12:1280, 13:1262, 14:891, 15:530, 16:289, 17:151, 18:77, 19:39, 20:20, 21:10, 22:5, 23:3, 24:1, 25:1
82		6:1, 9:2, 10:113, 11:684, 12:1290, 13:1283, 14:910, 15:542, 16:296, 17:155, 18:79, 19:40, 20:20, 21:10, 22:5, 23:3, 24:1, 25:1
83	41	6:1, 9:2, 10:109, 11:679, 12:1300, 13:1303, 14:928, 15:555, 16:303, 17:159, 18:81, 19:41, 20:21, 21:10, 22:5, 23:3, 24:1, 25:1
84		6:1, 9:2, 10:105, 11:673, 12:1310, 13:1324, 14:947, 15:567, 16:310, 17:162, 18:83, 19:42, 20:21, 21:11, 22:5, 23:3, 24:1, 25:1
85	42	6:1, 9:2, 10:101, 11:668, 12:1319, 13:1344, 14:966, 15:580, 16:318, 17:166, 18:85, 19:43, 20:22, 21:11, 22:5, 23:3, 24:1, 25:1
86		6:1, 9:2, 10:98, 11:662, 12:1328, 13:1364, 14:985, 15:592, 16:325, 17:170, 18:87, 19:44, 20:22, 21:11, 22:6, 23:3, 24:1, 25:1
87	43	6:1, 9:1, 10:95, 11:657, 12:1337, 13:1385, 14:1004, 15:605, 16:332, 17:174, 18:89, 19:45, 20:23, 21:11, 22:6, 23:3, 24:1, 25:1
88		6:1, 9:1, 10:91, 11:651, 12:1345, 13:1405, 14:1023, 15:618, 16:339, 17:178, 18:91, 19:46, 20:23, 21:12, 22:6, 23:3, 24:1, 25:1
89	44	6:1, 9:1, 10:88, 11:645, 12:1353, 13:1425, 14:1042, 15:631, 16:347, 17:182, 18:93, 19:47, 20:24, 21:12, 22:6, 23:3, 24:1, 25:1
90		6:1, 9:1, 10:85, 11:639, 12:1361, 13:1445, 14:1061, 15:644, 16:354, 17:186, 18:95, 19:48, 20:24, 21:12, 22:6, 23:3, 24:2, 25:1
91	45	6:1, 9:1, 10:82, 11:633, 12:1369, 13:1465, 14:1080, 15:657, 16:362, 17:190, 18:97, 19:49, 20:25, 21:12, 22:6, 23:3, 24:2, 25:1
92		6:1, 9:1, 10:79, 11:627, 12:1376, 13:1485, 14:1099, 15:670, 16:370, 17:194, 18:100, 19:50, 20:25, 21:13, 22:6, 23:3, 24:2, 25:1
93	46	6:1, 9:1, 10:76, 11:621, 12:1383, 13:1505, 14:1119, 15:683, 16:378, 17:199, 18:102, 19:51, 20:26, 21:13, 22:6, 23:3, 24:2, 25:1
94		6:1, 9:1, 10:74, 11:615, 12:1390, 13:1524, 14:1138, 15:697, 16:385, 17:203, 18:104, 19:53, 20:26, 21:13, 22:7, 23:3, 24:2, 25:1
95	47	6:1, 9:1, 10:71, 11:609, 12:1396, 13:1544, 14:1158, 15:710, 16:393, 17:207, 18:106, 19:54, 20:27, 21:14, 22:7, 23:3, 24:2, 25:1
96		6:1, 9:1, 10:68, 11:602, 12:1403, 13:1563, 14:1178, 15:724, 16:401, 17:211, 18:109, 19:55, 20:28, 21:14, 22:7, 23:4, 24:2, 25:1
97	48	6:1, 9:1, 10:66, 11:596, 12:1409, 13:1583, 14:1197, 15:737, 16:409, 17:216, 18:111, 19:56, 20:28, 21:14, 22:7, 23:4, 24:2, 25:1
98		6:1, 9:1, 10:64, 11:590, 12:1414, 13:1602, 14:1217, 15:751, 16:417, 17:220, 18:113, 19:57, 20:29, 21:14, 22:7, 23:4, 24:2, 25:1
99	49	6:1, 9:1, 10:61, 11:583, 12:1420, 13:1621, 14:1237, 15:765, 16:426, 17:225, 18:115, 19:58, 20:29, 21:15, 22:7, 23:4, 24:2, 25:1
100		6:1, 10:59, 11:577, 12:1425, 13:1640, 14:1257, 15:779, 16:434, 17:229, 18:118, 19:60, 20:30, 21:15, 22:8, 23:4, 24:2, 25:1

Miscellaneous observations

I used 23andMe's genetic testing for me and my family, and found a cousin I share 0.31% of my DNA with. However, my son shares 0.48% of his DNA with that same cousin. How can that be? Does that mean my wife and I are closely related? Probably not. More likely, I'm a distant cousin on his mother's side, and my wife is a distant cousin on his father's side. That doesn't imply that my wife and I are related at all, yet it still allows our son to have more DNA in common with him than either of us has.

I wonder what the mechanical process is for meiosis. It sounds you get two pairs, then you exchange the ends of one side of each of those pairs to force crossover. Maybe the other ends are twisted around, or moved independently in a fixed manner. I don't know if both ends are twisted or just one end, but the middle doesn't seem to be moved in a controlled manner.

The small number of genetic ancestors implies it is much easier to not be inbred according to genetic ancestors than by genealogical ancestors. You had a trillion genealogical ancestors 40 generations back, which far exceeds the total number of people who have ever existed, so most of your ancestors appear many many times in your genealogical tree. But you had under 3000 genetic ancestors 40 generations back (and under 7000 at 100 generations back). It's quite feasible for all your genetic ancestors to have been distinct for as far back as it's practical to go.

Another upshot of having so few genetic ancestors is that purebloods are possible. Even if some of your ancestors are from outside the desired pedigree, they don't count if you don't have any of their DNA. So you could identify and maintain 100% pureblood Native Americans. What's more, you don't have to start with purebloods to get purebloods. You could produce pureblood aurochs, or pureblood tarpans, or pureblood Tasmanian aborigines, even though none exist today. All you need is a full set of the genome of the extinct race still mixed into today's population, be able to identify short sequences of the whole genome, then do a breeding program. First you breed to maximize desired genetic content, then you breed to eliminate the few remaining non-desired genetic stretches. Another upshot is it's easy to produce creatures that are fully inbred (100% homozygous) (provided they don't die due to being inbred): you breed those the same way. I am not sure if any Y chromosomes exist in living people for Tasmanian aborigines, so maybe only purebred Tasmanian aboriginal women are possible. I hear that Neanderthals do not have any trace of large sections of their genome left in humanity today, so Neanderthals cannot be fully reproduced.

Being purebred is close to the opposite of not being inbred, but not quite. By the birthday paradox, if you expect n genetic ancestors however many generations back and nobody was more than n^-2 of your genealogical ancestors, then it's over 50% chance that all your genetic ancestors that far back are distinct. Being purebred without being inbred requires having a large breeding pool, and to breed exclusively from that pool. For example, to be purebred yet have at least 50% chance of a random mate not being genetically related to you, you need a pool of at least 3000*3000 = 9 million genetic ancestors 40 generations back or at least 7000 * 7000 = 49 million genetic ancestors 100 generations back.

Being inbred is not hereditary: if you take two completely homozygous (inbred) individuals who have no stretches in common, their children will be 100% heterozygous (not inbred) (mutts). At the lowest functional level, humans code for 23,000 proteins, so being completely not inbred requires 2 distinct variants for each of those 23,000 proteins, and having two totally unrelated totally non-inbred individuals requires 4 variants for each protein. And having 50% of possible mates have completely unrelated proteins requires a pool of at least 23,000*23,000 = 529 million possible mates to to choose from. Males are always inbred (homozygous) in the X chromosome, because they only have 1 copy of that, this is unavoidable.

Human genetic diversity
Everyone is unique
Telescope array
More such armchair designs
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