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ChrisR
07-28-2015, 12:41 AM
A Genome-Wide Association Study Identifies Five Loci Influencing Facial Morphology in Europeans
http://journals.plos.org/plosgenetics/article?id=10.1371/journal.pgen.1002932

Modeling 3D Facial Shape from DNA
http://journals.plos.org/plosgenetics/article?id=10.1371/journal.pgen.1004224
From my genetic education (see links to studies above) I never heard a scientific source that claimed something else then Autosomes affected the human facial phenotype (Chromosomes 1, 2, 3, 5, 10).

However I hear claims that Y-DNA influences the skull and facial features based on personal observations of ancestor pictures etc. and also receive questions about this topic.

I want to bring this topic up here to possibly receive further sources not connecting any uniparental DNA to Cranio-Facial features or better excluding them explicitly from contribution.

AJL
07-28-2015, 06:00 AM
^ Yes, as far as we know the genetic variation corresponding to facial morphology comes entirely from the autosomes.

Besides the autosomal factors there is also a considerable role for epigenetic variation. Even as-yet unidentified epigenetic factors associated with one's year of birth appear to cause variation in appearance (http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2667914/).

Volat
07-28-2015, 06:56 AM
This is from Nonmetric cranial trait variation and Population history of Medieval East Slavic Tribes (2013), Alla A. Movsesian


Nonmetric traits

The biological affinities among samples were studied by means of cranial nonmetric traits. Nonmetric traits 497 have been widely and successfully used as phenetic markers to assess the degree of biological differentiation and to evaluate the genetic relationships among ancient populations (e.g., Berry and Berry, 1967; Ossenberg, 1976; Buikstra, 1980; Kato et al., 1995; Alt and Vach, 1995; Lahr, 1996; Dodo et al., 1998; Gonzalez et al., 2001; Stefan and Chapman, 2003; Sutter and Mertz, 2004; Baholdina, 2005; Stojanowski and Schillaci, 2006; Hanihara, 2008; Ricaut and Waelkens, 2008; Hanihara et al., 2012; Nikita et al., 2012). Indirect evidence suggests that variation in skull structure appears in the course of normal development and is largely determined by genetic factors (Torgensen, 1951; Sjďvold, 1984; R€ osing, 1986). Studies conducted on mice (Gr€uneberg, 1963; Leamy, 1974; Richtsmeier and McGrath, 1986), rhesus monkeys (Cheverud and Buikstra, 1981aa, 1981bb; McGrath et al., 1984), and humans (Gr€uneberg, 1963; Berry, 1968; Berry and Berry, 1971; Sjďvold, 1984; Tyrell, 2000; Veleminsky and Dobis ıkova, 2005; Carson, 2006) have showed that many cranial traits are highly heritable. The hereditary nature of nonmetric cranial traits speaks to the stability of their frequencies in populations over time, and to the congruence of nonmetric trait data with archaeological and historical data (Movsesian and Kochar, 2004; Movsessyan, 2012). It has been shown that phenotypic variation reflects genotypic variation between groups, and phenotypic distances correspond to actual genetic distances between populations (Hanihara et al., 2003; Relethford, 2004; Roseman, 2004; Harvati and Weaver, 2006; Manica et al., 2007; Hanihara, 2008; Smith, 2009; Von Cramon-Taubadel, 2009; Ricaut et al., 2010). The analysis of nonmetric-trait frequency distributions in populations from different regions of the world has showed that classification trees constructed from phenotypic data correspond to those based on classical genetic markers (Hanihara et al., 2003, Hanihara, 2008; Movsesian, 2005). Moreover, a recent study by Ricaut et al. (2010) confirmed that nonmetric traits are correlated with genetic data (mtDNA, Y-chromosome, and autosomal short tandem repeats) and can provide an alternative to genetic markers.

Ricaut FX, Auriol V, Cramon-Taubadel N, Keyser C, Murail P, Ludes B, Crub ezy E. 2010. Comparison between morphological and genetic data to estimate biological relationship: the case of the Egyin Gol necropolis (Mongolia). Am J Phys Anthropol 143:355–364.

J Man
07-28-2015, 12:09 PM
Skull and facial shapes will never be as accurate as DNA is for tracing population movements. Skull and facial types are more like compliments to DNA.

Kale
07-28-2015, 01:08 PM
I'm also assuming the sex chromosomes would have an effect on hormone levels...which undoubtedly can effect appearance.

AJL
07-28-2015, 05:06 PM
a recent study by Ricaut et al. (2010) confirmed that nonmetric traits are correlated with genetic data (mtDNA, Y-chromosome, and autosomal short tandem repeats) and can provide an alternative to genetic markers.

Correlation does not imply causation.

You can link facial appearances statistically with postal codes/zip codes, and find relationships, but this does not mean their appearance is caused by the number you write on an envelope when you send them a letter.

Volat
07-28-2015, 07:50 PM
Correlation does not imply causation.

You can link facial appearances statistically with postal codes/zip codes, and find relationships, but this does not mean their appearance is caused by the number you write on an envelope when you send them a letter.

That's true . But one can still use zip codes categories to predict certain patterns in physical appearance of people living in certain districts if there is a correlation between the two variables. I would also not be bluntly disregarding the usefulness of the nonmetric traits as an alternative to genetic markers simply pointing to the fact there was no causation established before reading the study. And that is the conclusion - the nonmetric can be used as an alternative to the genetic marker, rather than Y-chromosome, mtDNA markers are responsible (causing) for certain physical characteristics.

Shaikorth
07-29-2015, 06:55 AM
Uniparentals extremely unlikely, even autosomals don't correlate so good with craniofacial features. The following tree is average hierarchical clustering of population correlations based on 37 cranial measures, from 2011 study "A Geographic Cline of Skull and Brain Morphology among Individuals of European Ancestry". One can see some broad groupings that correlate with geography and ancestry, but anyone somewhat familiar with European genetics can see there are many obvious divergences from a tree based on uniparentals or autosomes.

http://oi61.tinypic.com/k2olsn.jpg

The recent Paleoamerican study by Raghavan et al. did a global analysis of craniometry and there we see things like Austrians clustering with Buryats and not Norse or Hungarians, on both their tree and PCA (fig. S41).

ChrisR
08-20-2015, 12:45 PM
Recent publication based on Iceland data analysis as posted by Debbie C.K.:

This is an interesting study using the deCODE dataset from Iceland. The paper is paywalled but here is a key quote from the discussion: “Despite a modest number of individuals we found six holistic facial characteristics 159 predicted with statistical significance. We find face width (found previously to be associated to specific 160 SNPs by), fullness of female lips, and a slight variation in mouth width in men as the features 161 with the greatest potential in the context of facial trait prediction. For women we additionally find eye distance, eye size and eyebrow width as predictable to a smaller degree. The fact that we achieve a 163 better performance when predicting on genders separately could be caused by differences in facial features 164 between men and women.”
Predicting facial characteristics from complex polygenic variations
http://www.fsigenetics.com/article/S1872-4973%2815%2930059-4/abstract

If anyone is able to get information on the genome position of the discussed SNPs/Variants I would appreciate.

panhudist
06-25-2016, 07:44 AM
not much