Cross-Population Analysis of Breast CancerTranscriptomics: Comparative Insights Between Caucasian and Indian Patients

Ethnic diversity in breast cancer often results in overlapping genetic profiles, complicating prognosis despite evolving classification methods. The present study examines transcriptomic variations between Caucasian and Indian populations through a cross-population analysis to assess whether genes differentially expressed in breast cancer among Caucasian women show similar patterns in Indian women. Utilizing datasets from middle-aged Caucasian women with breast cancer (SRA Project: SRP375823), we performed RNA-seq analysis using the GATK and Tuxedo II pipelines to identify differentially expressed genes, followed by functional enrichment analysis. We identified eleven genes— mTOR, BARD1, RAD50, ADIPOQ, PMS2, ARID5B, NHERF1, SPEN, SDHB, MYH10 , and APC —that were differentially expressed and significantly associated with breast cancer in the Caucasian population. To assess the impact of ethnic variability on gene expression, we analyzed the expression of the aforementioned genes associated with breast cancer in Indian breast cancer patients. We found that mTO R, BARD1, RAD50 , and ADIPOQ were upregulated, and PMS2 was downregulated in both populations, suggesting their universal role in breast cancer progression. However, ARID5B, NHERF1, SPEN, SDHB , and APC displayed population-specific differences, with downregulation observed only in Caucasian patients and no difference in Indian populations. These findings reveal ethnic differences in breast cancer gene expression, highlighting the need to consider both universal and population-specific variations in research and treatment strategies.