Vol. 11, Special Issue 11 (2022)

Author(s):
Aishwarya Dash, Dhandapani S, ID Gupta and Jayakumar Sivalingam

Abstract:
Genetic variation is the difference between individuals detected at molecular level and it is classified into different kinds based on number of nucleotides involved. Structural variations are variations observed due to mutation and genetic recombination in DNA segments (polynucleotide). Copy number variation is an unbalanced structural variation due to loss or gain of DNA fragments varying from 50bp to several mega base pair length. It covers a higher portion of genomic sequence and has higher mutation rate than SNPs. CNVs involve one or more genes and are accountable for change in their structures and quantity and may create new genes. There are several mechanisms such as, non-allelic homologous recombination, non-homologous end-joining, fork stalling and template switching and L1-mediated retro transposition for CNV genesis due to like dele­tion, duplication, inversions, and translocations of the genes. With the advancement of technology, different techniques (Conventional methods, Array based methods, Next generation Sequencing) are used to detect copy number variations in various livestock species associated with several traits. Hence, CNVs are potentially greater effect in variation and can be considered to be promising causal genetic markers of economic importance.