Common polymorphisms in WNT10A affect tooth morphology as well as hair shape

Area of Science:

• Genetics and Evolutionary Biology
• Developmental Biology
• Anthropology

Background:

• Hair and teeth are ectodermal appendages sharing common molecular developmental pathways.
• Previous research linked EDAR gene variations to hair and tooth morphology.
• Single-nucleotide polymorphisms (SNPs) near several genes, including WNT10A, are associated with hair morphology.

Purpose of the Study:

• To investigate if hair morphology-associated SNPs also influence dental characteristics.
• To identify specific genetic variants impacting tooth size and non-metric traits.
• To explore the pleiotropic effects of WNT10A gene variations on ectodermal appendages.

Main Methods:

• Genotyping of Japanese and Korean subjects for SNPs previously associated with hair morphology.
• Measurement of metric dental traits (crown size) and evaluation of non-metric dental traits from plaster casts.
• Statistical association analysis between identified SNPs and dental phenotypes.

Main Results:

• A significant association was found between a WNT10A SNP (rs7349332) and dental crown size.
• Further analysis of WNT10A SNPs identified rs10177996 as strongly associated with dental traits.
• The derived allele of rs10177996, linked to larger teeth, shows higher frequency in Eurasians compared to Africans.

Conclusions:

• Common variations in the WNT10A gene exhibit pleiotropic effects, influencing the morphology of both hair and teeth.
• WNT10A SNPs represent key genetic factors in the evolution of ectodermal appendage morphology.
• This research highlights WNT10A's role in human morphological variation across different populations.