From Visscher and colleagues:
Population genetic differentiation of height and body mass index across EuropeAcross-nation differences in the mean values for complex traits are common1, 2, 3, 4, 5, 6, 7, 8, but the reasons for these differences are unknown. Here we find that many independent loci contribute to population genetic differences in height and body mass index (BMI) in 9,416 individuals across 14 European countries. Using discovery data on over 250,000 individuals and unbiased effect size estimates from 17,500 sibling pairs, we estimate that 24% (95% credible interval (CI) = 9%, 41%) and 8% (95% CI = 4%, 16%) of the captured additive genetic variance for height and BMI, respectively, reflect population genetic differences. Population genetic divergence differed significantly from that in a null model (height, P < 3.94 × 10−8; BMI, P < 5.95 × 10−4), and we find an among-population genetic correlation for tall and slender individuals (r = −0.80, 95% CI = −0.95, −0.60), consistent with correlated selection for both phenotypes. Observed differences in height among populations reflected the predicted genetic means (r = 0.51; P < 0.001), but environmental differences across Europe masked genetic differentiation for BMI (P < 0.58).
ReplyDeleteSomewhat related:
Height-reducing variants and selection for short stature in Sardinia
We report sequencing-based whole-genome association analyses to evaluate the impact of rare and founder variants on stature in 6,307 individuals on the island of Sardinia. We identify two variants with large effects. One variant, which introduces a stop codon in the GHR gene, is relatively frequent in Sardinia (0.87% versus <0.01% elsewhere) and in the homozygous state causes Laron syndrome involving short stature. We find that this variant reduces height in heterozygotes by an average of 4.2 cm (−0.64 s.d.). The other variant, in the imprinted KCNQ1 gene (minor allele frequency (MAF) = 7.7% in Sardinia versus <1% elsewhere) reduces height by an average of 1.83 cm (−0.31 s.d.) when maternally inherited. Additionally, polygenic scores indicate that known height-decreasing alleles are at systematically higher frequencies in Sardinians than would be expected by genetic drift. The findings are consistent with selection for shorter stature in Sardinia and a suggestive human example of the proposed 'island effect' reducing the size of large mammals.
OMG!
ReplyDeletea whopping 24% of the additive genetic variance.
TOTALLY
RETARDED.
n/a is mathematically RETARDED if he thinks this study is anything other than MEANINGLESS.
and unbiased effect size estimates from 17,500 sibling pairs
ReplyDeleteGAY!
TOTALLY GAY!
LIBERACE GAY!
https://www.youtube.com/watch?v=r0gVdOJIu1c
caps lock mania
ReplyDeleteI am slightly loathe to comment here, since other than n/a, most commentators here seem marginally sane.
ReplyDeleteYet, to be clear on what this shows, essentially 1cm, or 1/2 inch, in genetic height differentiation between the Italian and Dutch samples. The most extremely different samples. This is not unbelievable. By any means.
As to the BMI, bear in mind that BMI =! obesity or fat mass. This signal, which spans a narrow BMI range, tracks that tall populations in Europe seem to have been under less selection for body mass relative to height. And this may well reflect (perhaps probably reflects) lean mass such as muscle, skin, internal organs, to a large degree rather than difference in body fat %.
So Italians (and Southern populations) genetically around a cm less tall, and probably fatter and more muscular for their height, to a small degree. Or in the case of women, curvier in all likelihood (larger buttocks / breasts). Nordic groups are a bit taller, and also rather a little more inclined to the rangy and skinny. Seems this reflects reality.