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Updated: Jul 16, 2026
09:26
Quantification of Orofacial Phenotypes in Xenopus
Published on: November 6, 2014
Complex segregation analysis of two principal components derived from horizontal and vertical head size traits
Sergey Ermakov1, Eugene Kobyliansky, Gregory Livshits
1Department of Anatomy and Anthropology, Human Population Biology Research Unit Sackler Faculty of Medicine, Tel Aviv University, Tel Aviv, Israel.
Annals of Human Biology
|March 27, 2007
Summary
Head size is inherited through major genes. Horizontal and vertical head dimensions are each influenced by distinct major genes, with some shared minor genes contributing to variation.
Area of Science:
- Human genetics
- Quantitative genetics
- Craniofacial biology
Background:
- Genetic factors significantly influence individual differences in head size.
- The inheritance patterns of craniofacial traits in healthy individuals remain largely uncharacterized.
Purpose of the Study:
- To determine the mode of inheritance for horizontal (HOC) and vertical (VEC) head dimensions.
- To investigate if a single major gene controls these craniofacial traits.
Main Methods:
- Complex segregation analysis was performed on 1406 individuals from 357 families.
- Two principal components, HOC and VEC, derived from 10 head measurements, were analyzed.
Main Results:
- Mendelian transmission was supported for both HOC and VEC.
- Major genes accounted for 54.0% of HOC variance and 45.6% of VEC variance.
- Additive gene action was suggested, with no evidence for a shared major gene between HOC and VEC.
Conclusions:
- Head size in horizontal and vertical dimensions is primarily controlled by two separate major genes.
- Minor effect genes, partially shared between HOC and VEC, also contribute to head size variation.
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