Frequent copy number variants in a cohort of Mexican-Mestizo individuals

Background: The human genome presents variation at distinct levels, Copy number variants (CNV) are DNA segments of various lengths in bp that are present at a variable number of copies compared to a reference genome. CNV analysis has been done in almost all human populations and most of them have no apparent influence on the phenotype, yet some of them usually long sized, has been associated with pathologies. Recently however, the detection of common and benign CNV within different ethnic populations is becoming increasingly relevant as it helps in discerning real pathological variants and thus avoiding misinterpretations. The aim of this work is to describe four CNV frequently found in a cohort of 147 Mexican-Mestizo individuals. Results: : In this study we found four CNV 2p11.2, 8p11.22, 14q32.33 and 15q11.2, with a high frequency in the Mexican population when contrasted with the HapMap reference (ChAS), while when used an ethnically related population as a reference, the differences are reduced or disappear. The population studied does not show inbreeding or consanguinity. Conclusion: CNV-type polymorphisms have frequencies that vary according to the ethnic group studied. It highlights the importance of analyzing the CNV of the studied individuals, with a reference group that -as far as possible- share the same ethnicity. These findings should be considered to avoid false associations of CNV with pathological conditions.