PHENOTYPIC TRAIT FREQUENCIES IN AN UNDERGRADUATE STUDENT COHORT FROM THANE DISTRICT, MAHARASHTRA
DOI:
https://doi.org/10.69980/a2azj993Keywords:
Phenotypic traits, Population genetics, Thane District, ABO blood groups, Allele frequencies, AnthropometryAbstract
The phenotypic landscape of the Thane District student population (N=500) reveals significant genetic heterogeneity within this cosmopolitan Indian subcontinent hub. In this study eleven variables were recorded per participant: weight (kg), height (cm), double chin (yes/no), thumb cross dominance (left/right), ABO/Rh blood group (self-reported from medical records), earlobe type (free or Unjointed / joined), widow's peak (yes/no), Body colour (Skin Pigmentation) (fair/brown/dark), hair structure (straight/curly), hair colour (black/brown/hazel), and eye colour (black/brown/hazel) respectively. Dietary behaviour was also studied among vegetarians and non-vegetarians (both). This cross-sectional study identifies Blood group A+ as the most prevalent phenotype (34.2%), while the Rh-negative frequency (20.4%) notably exceeds national averages, suggesting localized allele frequencies or ancestral admixture. Morphological analysis of earlobe morphology (51% joined) and presence of widow’s peak (43.8%) aligns with South Asian benchmarks, though their distribution challenges strict Mendelian inheritance models in favor of polygenic or oligogenic patterns. Pigmentation traits remain dominated by ancestral alleles, with black hair (80.6%) and black eyes (59.8%) being near-universal. Anthropometric data confirmed significant sexual dimorphism in height (p < .001), while thumb-crossing dominance showed a near-even split (50.8% left), reflecting the trait's developmental ambiguity. This dataset, integrated with statistical analysis such as Chi-square tests and linear regression, provides a vital baseline for population genetics. Furthermore, it serves as a curated resource for outcome-based education aligned with the NEP-2020 framework, bridging the gap between theoretical evolutionary biology and observable human phenotypic traits in a diverse regional cohort.
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