September 19, 2009

Genetics and environment contributions to craniofacial phenotypes of Belgians

Hum Biol. 2008 Dec;80(6):637-54.

Contribution of genetics and environment to craniofacial anthropometric phenotypes in Belgian nuclear families.

Jelenkovic A, Poveda A, Susanne C, Rebato E.

In this study we estimate relative genetic and environmental influences on head-related anthropometric phenotypes. The subject group consisted of 119 nuclear families living in Brussels, Belgium, and included 238 males and 236 females, ages 17 to 72 years. Two factor analyses with varimax rotation (the first one related to facial measurements and the second one to overall head morphology) were used to analyze 14 craniofacial size traits. The resulting four synthetic traits [HFCF, VFCF, HDF1, and HDF2-horizontal (breadth) and vertical (height) facial factors and two head horizontal (breadth) factors, respectively] were used as summary variables. Maximum heritabilities (H2) were estimated for all studied traits, and variance components analysis was applied to determine the contribution of genetics and environment on the four craniofacial factors. In addition, we examined the covariations between the face (HFCF and VFCF) and head-related factors (HDF1 and HDF2), separately. Quantitative genetic analysis showed that HFCF, VFCF, HDF1, and HDF2 variation was appreciably attributable to additive genetic effects, with heritability (h2) estimates of 67.62%, 54.97%, 70.76%, and 65.05%, respectively. The three variance components reflecting a shared familial environment were nonsignificant for these four phenotypes. Bivariate analysis revealed significant additive and residual correlations for both pair of traits. The results confirm the existence of a significant genetic component determining the four craniofacial synthetic traits, and common genetic and environmental effects shared by the two face-related phenotypes and by the head-related ones.



Anonymous said...

Doesn't say much does it? Nature and nurture combine to in nuclear families and have an effect on appearance. Really!

Kepler said...

And why Brussels of all places? There are very few people who have lived there for more than 3 generations, they come from all around the world, more so than for many other capitals of Europe.

Maju said...

So genetics seems to influence cranial phenotype only in some 60%. That is quite relevant, specially as it probably deals with single-generation distances. The accumulative effects of non-genetic randomness could be brutal if I'm correct.