GENETIC POLYMORPHISM IN AGOUTI SIGNALING PROTEIN (ASIP) GENE AMONG SHEEP GENETIC GROUPS OF ANDHRA PRADESH
Loading...
![Thumbnail Image](assets/images/Item.jpg)
Files
Date
2022-09
Authors
Journal Title
Journal ISSN
Volume Title
Publisher
SRI VENKATESWARA VETERINARY UNIVERSITY TIRUPATI - 517 502. (A.P.) INDIA
Abstract
The sheep genetic resources of Andhra Pradesh shows a very clear distinct coat
colour pattern. Coat colour is an important economic trait in domestic sheep which vary
greatly due to hereditary and environmental factors. The coat colour phenotype is
influenced by a large number of genes involved in various stages of melanogenesis,
from the migration and maturation of the melanocytes to the production of melanin. The
agouti signaling pathway (ASIP) gene is a crucial gene that plays an important role in
coat colour determination in sheep through epistatic interaction with other genes. The
present study was conducted to provide insight into role of certain ASIP loci in coat
colour patterns in the sheep genetic groups of Andhra Pradesh.
Blood samples were collected from six sheep genetic groups of Andhra Pradesh.
Modified high salt method was used for the isolation of Genomic DNA. An allele
specific PCR assay was designed to study variation in the deletion locus D5 located on exon 2 of the gene. PCR-RFLP assay with PstI restriction enzyme was used to
determine the non-synonymous SNP (c.5172T>A) polymorphism. Departures from
Hardy-Weinberg equilibrium in each population were analyzed using a chi-square test
for both the loci. As the pattern of genotypes are not consistent with the genetic groups,
it is difficult to draw a conclusion with respect to D5 allele and its role in coat colour in
sheep genetic groups of Andhra Pradesh. In 5172T>A SNP, it is interesting to note that
how a black coat colour influencing allele under homozygous condition is producing
white coat colour in Nellore Palla. No single genetic group is associated with specific
genotype for either of the loci so, a total of nine possible combination of diplotypes
were scored. However, no specific diplotype is associated with the genetic group. From
this, it is plausibly deduced that the combination of wild type at the deletion locus and T
allele at the non-synonymous locus could plausibly be giving rise to the white coat
colour in these genetic groups except in Nellore Brown which may be due to
interactions with other coat colour loci. In order to get better understanding about
genetics of coat colour in the native sheep genetic groups of Andhra Pradesh, studies
involving coat colour loci other than ASIP gene and specific coat colour pattern of each
individual is necessary.
Description
THESIS