|(C;C)||2||straighter, thicker hair, and increased odds of having shovel-shaped incisors|
|(C;T)||1||increased odds of straighter, thicker hair as well as shovel-shaped incisors|
|(T;T)||0||common in clinvar|
The rs3827760(C) allele is far more prevalent in East Asians and Native Americans than in any other population, and it is used as such in ancestry tests [PMID 22749789]. There are at least four physical characteristics that have been linked to this allele, and pretty much all in a copy-dependent manner as well (inheriting both alleles leads to a stronger expression than inheriting one):
- Hair follicle thickness [PMID 18065779]
- Hair straightness (i.e. lack of curliness) [PMID 23793515]
- Shovel shaped incisors (teeth) [PMID 19804850]
- Mammary duct branching density 10.1073/pnas.1711788115
10.1038/ncomms10815 A genome-wide association scan in admixed Latin Americans identifies loci influencing facial and scalp hair features
10.1073/pnas.1711788115 Environmental selection during the last ice age on the mother-to-infant transmission of vitamin D and fatty acids through breast milk. This article postulates that the need for more Vitamin D in higher latitudes selected for this mutation during the last ice age (~18,000 - 28,000 years ago), since it increases the branching density of mammary ducts, and just by chance the mutation also happens to lead to shovel shaped incisors.
gnxp hair thickness for asians
gnxp blog tooth shape among asians
A picture of shovel shaped incisors is at http://www.flickr.com/photos/39602184@N02/3747590190/
[PMID 19804850] A Common Variation in EDAR Is a Genetic Determinant of Shovel-Shaped Incisors
[PMID 22648185] Effects of an Asian-specific nonsynonymous EDAR variant on multiple dental traits
|Disease||Hair morphology 1 not specified Hypohidrotic Ectodermal Dysplasia|
|CLNDBN||Hair morphology 1, hair thickness not specified Hypohidrotic Ectodermal Dysplasia, Dominant|
|CLNSRC||OMIM Allelic Variant UniProtKB (protein)|
|CLNACC||RCV000006216.3, RCV000174399.2, RCV000382959.1,|
[PMID 16255080] A haplotype map of the human genome.
[PMID 18561327] Enhanced ectodysplasin-A receptor (EDAR) signaling alters multiple fiber characteristics to produce the East Asian hair form.
[PMID 18817904] Japanese population structure, based on SNP genotypes from 7003 individuals compared to other ethnic groups: effects on population-based association studies.
[PMID 19737746] Population differentiation as an indicator of recent positive selection in humans: an empirical evaluation.
[PMID 22749789] Revision of the SNPforID 34-plex forensic ancestry test: Assay enhancements, standard reference sample genotypes and extended population studies.