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[OBG] Genetic and Environmental Determinants of IQ in Black, White, and Hispanic Amer

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(2014-Aug-21, 21:11:34)menghu1001 Wrote:
(2014-Aug-21, 19:58:04)Dalliard Wrote: ACE or ADE model fitting to twin data is limited in that C and D components cannot be simultaneously estimated


It's obvious. When rMZ is more than the half of rMZ, C is larger than 0. If rMZ is the half of rMZ, there no C and no D. When rMZ is lower than half of rMZ, there is D larger than 0. You can't have positive C and positive D at the same time. Thus, what's the limitation here ?


Let's say rMZ is 0.8 and rDZ is 0.3 (and there is no AM). This could be because there's D variance and no C variance. But it could as well be that there's both D and C variance but more D. In the classic twin design, C and D are confounded; they cannot be simultaneously estimated because of underidentification. You need additional types of relatives to estimate both C and D.

Quote:
(2014-Aug-21, 19:58:04)Dalliard Wrote: Moreover, assortative mating (AM) is not considered. What this means is that the estimates from these models cannot be correct.

ACE without taking account AM is worse doing than ADE without taking account AM. Unless you can prove there is no non-additive genetic effect, it is not justified to talk about A or h2 (narrow-sense). Remember that the interest of ADE is the decomposition of A and D components. Without this done, it's thus not justified to make claims about narrow h2 that has not been proven.


In IQ studies, rMZ is usually ≤2*rDZ, so models with D fit poorly and are not estimated. The model assumption that genetic variance is all A may be wrong, but that's what the data are usually consistent with.

Quote:I haven't read Vinkhuyzen et al. study but don't understand your argument : "their H2 estimate comes to about 80 percent, which is similar to h2 estimates from studies that assume only additive heredity and no AM".

Specifically, what are you referring to by h2 ? Is it the h2 from Falconer's computation ? (in general I hate using h2/H2 because I'm always confused with the two, even if I have read the descriptions many times) And the H2 of Vinkhuyzen is the heritability when taking account AM ? So, why are they saying "much of IQ heritability is non-additive" ?

H2=additive, dominance, and epistatic genetic effects

h2=A=additive genetic effects, usually estimated from MZ-DZ data with model fitting

Falconer's heritability is neither H2 nor h2 but it's closer to H2.

In Vinkhuyzen's preferred model, A=44%, D=27%, and AM=11%. AFAIK, the last should be interpreted as genetic variance. Summing them you get broad heritability H2=82%.
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Messages In This Thread
[OBG] Genetic and Environmental Determinants of IQ in Black, White, and Hispanic Amer - by Chuck - 2014-Jul-14, 06:25:48
RE: Genetic and Environmental Determinants of IQ in Black, White, and Hispanic Americans - by Emil - 2014-Jul-14, 10:45:09
RE: Genetic and Environmental Determinants of IQ in Black, White, and Hispanic Americans - by Meng Hu - 2014-Jul-14, 19:57:08
RE: Genetic and Environmental Determinants of IQ in Black, White, and Hispanic Americans - by Chuck - 2014-Jul-19, 22:37:13
RE: Genetic and Environmental Determinants of IQ in Black, White, and Hispanic Americans - by Chuck - 2014-Aug-05, 22:39:40
RE: Genetic and Environmental Determinants of IQ in Black, White, and Hispanic Americans - by Emil - 2014-Aug-07, 19:25:59
RE: Genetic and Environmental Determinants of IQ in Black, White, and Hispanic Americans - by Chuck - 2014-Aug-07, 22:27:33
RE: Genetic and Environmental Determinants of IQ in Black, White, and Hispanic Americans - by Chuck - 2014-Aug-08, 00:32:10
RE: Genetic and Environmental Determinants of IQ in Black, White, and Hispanic Americans - by Chuck - 2014-Aug-19, 03:11:37
RE: Genetic and Environmental Determinants of IQ in Black, White, and Hispanic Americans - by Emil - 2014-Aug-08, 00:29:43
RE: Genetic and Environmental Determinants of IQ in Black, White, and Hispanic Americans - by Emil - 2014-Aug-19, 09:36:33
RE: Genetic and Environmental Determinants of IQ in Black, White, and Hispanic Americans - by Chuck - 2014-Aug-19, 19:22:42
RE: Genetic and Environmental Determinants of IQ in Black, White, and Hispanic Americans - by Duxide - 2014-Aug-19, 19:33:48
RE: Genetic and Environmental Determinants of IQ in Black, White, and Hispanic Americans - by Chuck - 2014-Aug-19, 20:27:44
RE: Genetic and Environmental Determinants of IQ in Black, White, and Hispanic Americans - by Duxide - 2014-Aug-19, 20:56:25
RE: Genetic and Environmental Determinants of IQ in Black, White, and Hispanic Americans - by Emil - 2014-Aug-19, 21:23:08
RE: Genetic and Environmental Determinants of IQ - by Meng Hu - 2014-Aug-21, 01:11:58
RE: Genetic and Environmental Determinants of IQ in Black, White, and Hispanic Americans - by Chuck - 2014-Aug-21, 01:25:25
RE: Genetic and Environmental Determinants of IQ in Black, White, and Hispanic Americans - by Meng Hu - 2014-Aug-21, 02:29:13
RE: Genetic and Environmental Determinants of IQ - by Dalliard - 2014-Aug-21, 19:58:04
RE: Genetic and Environmental Determinants of IQ - by Meng Hu - 2014-Aug-21, 21:11:34
RE: Genetic and Environmental Determinants of IQ in Black, White, and Hispanic Americans - by Chuck - 2014-Aug-21, 23:43:11
RE: Genetic and Environmental Determinants of IQ in Black, White, and Hispanic Americans - by Duxide - 2014-Aug-21, 22:57:35
RE: Genetic and Environmental Determinants of IQ - by Dalliard - 2014-Aug-21, 23:45:22
RE: Genetic and Environmental Determinants of IQ - by Meng Hu - 2014-Aug-22, 04:19:42
RE: Genetic and Environmental Determinants of IQ in Black, White, and Hispanic Americans - by Chuck - 2014-Aug-22, 04:25:14
RE: [OBG] Genetic and Environmental Determinants of IQ in Black, White, and Hispanic Amer - by Meng Hu - 2014-Sep-02, 23:40:26
RE: [OBG] Genetic and Environmental Determinants of IQ in Black, White, and Hispanic Amer - by Chuck - 2014-Sep-03, 02:48:14
RE: [OBG] Genetic and Environmental Determinants of IQ in Black, White, and Hispanic Amer - by Meng Hu - 2014-Sep-07, 01:49:42
RE: [OBG] Genetic and Environmental Determinants of IQ in Black, White, and Hispanic Amer - by Chuck - 2014-Sep-07, 19:35:52
RE: [OBG] Genetic and Environmental Determinants of IQ in Black, White, and Hispanic Amer - by Duxide - 2014-Sep-08, 13:02:31
RE: [OBG] Genetic and Environmental Determinants of IQ in Black, White, and Hispanic Amer - by Chuck - 2014-Sep-08, 15:16:27
RE: [OBG] Genetic and Environmental Determinants of IQ in Black, White, and Hispanic Amer - by Emil - 2014-Sep-07, 21:44:22
RE: [OBG] Genetic and Environmental Determinants of IQ in Black, White, and Hispanic Amer - by Chuck - 2014-Sep-07, 23:34:54
RE: [OBG] Genetic and Environmental Determinants of IQ in Black, White, and Hispanic Amer - by Emil - 2014-Sep-07, 23:51:24
RE: [OBG] Genetic and Environmental Determinants of IQ in Black, White, and Hispanic Amer - by Meng Hu - 2014-Sep-08, 00:21:20
RE: [OBG] Genetic and Environmental Determinants of IQ in Black, White, and Hispanic Amer - by Emil - 2014-Sep-08, 00:36:38
RE: [OBG] Genetic and Environmental Determinants of IQ in Black, White, and Hispanic Amer - by Emil - 2014-Sep-08, 15:04:06
RE: [OBG] Genetic and Environmental Determinants of IQ in Black, White, and Hispanic Amer - by Duxide - 2014-Sep-08, 17:48:27
RE: [OBG] Genetic and Environmental Determinants of IQ in Black, White, and Hispanic Amer - by Duxide - 2014-Sep-08, 18:01:30
RE: [OBG] Genetic and Environmental Determinants of IQ in Black, White, and Hispanic Amer - by Chuck - 2014-Sep-08, 19:44:52
RE: [OBG] Genetic and Environmental Determinants of IQ in Black, White, and Hispanic Amer - by Duxide - 2014-Sep-08, 19:48:12
RE: [OBG] Genetic and Environmental Determinants of IQ in Black, White, and Hispanic Amer - by Chuck - 2014-Sep-11, 23:19:01
RE: [OBG] Genetic and Environmental Determinants of IQ in Black, White, and Hispanic Amer - by Duxide - 2014-Sep-12, 10:53:22
RE: [OBG] Genetic and Environmental Determinants of IQ - by Dalliard - 2014-Sep-09, 21:25:33
RE: [OBG] Genetic and Environmental Determinants of IQ in Black, White, and Hispanic Amer - by Meng Hu - 2014-Sep-10, 01:12:35
RE: [OBG] Genetic and Environmental Determinants of IQ - by Dalliard - 2014-Sep-11, 18:27:00
RE: [OBG] Genetic and Environmental Determinants of IQ in Black, White, and Hispanic Amer - by Emil - 2014-Sep-11, 23:29:03
RE: [OBG] Genetic and Environmental Determinants of IQ in Black, White, and Hispanic Amer - by Chuck - 2014-Sep-11, 23:35:43
RE: [OBG] Genetic and Environmental Determinants of IQ in Black, White, and Hispanic Amer - by Emil - 2014-Sep-11, 23:44:40
RE: [OBG] Genetic and Environmental Determinants of IQ in Black, White, and Hispanic Amer - by Meng Hu - 2014-Sep-12, 01:30:14
RE: [OBG] Genetic and Environmental Determinants of IQ in Black, White, and Hispanic Amer - by Emil - 2014-Sep-12, 02:26:19
RE: [OBG] Genetic and Environmental Determinants of IQ in Black, White, and Hispanic Amer - by Duxide - 2014-Sep-12, 22:59:24
RE: [OBG] Genetic and Environmental Determinants of IQ in Black, White, and Hispanic Amer - by Chuck - 2014-Sep-14, 21:11:40
 
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