Relationship to Physical Traits and their Genetic Differences Among Individuals
DOI:
https://doi.org/10.17977/um067v6i42026p5Keywords:
Genetic Variation, Human Traits, Polygenic Traits, Mendelian Traits, Eye Color, Hair Type, Height, Epigenetics, Human DiversityAbstract
Human diversity is based on genetic variation, which determines a vast amount of physical characteristics such as the color of eyes, hair type, pigmentation of the skin, height and disease susceptibility. This review will be looking at the existing literature regarding the genetic differences among individuals and how they relate to observable traits. It emphasizes the contribution of mutations, gene recombination and chromosome variations in the production of specific genotypes and the role of environmental and epigenetic factors in the expression of the phenotype. There are specific genes, e.g. OCA2 and HERC2 that control the color of the eye, EDAR and TCHH that control the type of hair, and several polygenic loci that control the height and the pigmentation of the skin are discussed to illustrate the genetic origin of traits. The gaps in existing research also include the lack of knowledge on polygenic interactions, underrepresentation of diverse populations, and lack of literature on the effect of genes and the environment and epigenetics. Future research recommendations include the need to adopt interdisciplinary studies, longitudinal studies, and large-scale population studies to improve insights on human diversity. The importance of knowing the genetic variation is paramount to personalized medicine, anthropology, and population health.
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Copyright (c) 2026 Sabah Attwan Kazi, Salim Dakhil Rashid Rashid, Ahmed Rashid Tubena
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