Molecular detection of selected genetic polymorphisms in growth hormone and insulin like growth factor 1 genes in indigenous sudanese baggara cattle

Abstract

The study involved 127 bulls of two geographically separate strains of Sudanese Baggara zebu cattle (Nyalawi and Mesairi). The target was to investigate two polymorphisms in growth hormone gene (M57764) and insulin like growth factor1 gene (000162.1). PCR-RFLP was used to genotype DNA samples and DNA sequencing was used to check the accuracy of genotyping results using selected samples. Available sequences were analyzed using BioEdit and MEGA6 softwares. Some population genetic measures in the two strains of Baggara zebu cattle were investigated. PCR-RFLP revealed that the two Baggara cattle strains have high genetic similarity at position 2141C>G of the GH1 gene (monomorphic showing the ancestral allele C/C). There were no differences between the two strains at position -472C>T of the IGF-1 gene promoter. The mutant homozygote (TT) was detected in the Mesairi strain only with a frequency of 0.016. The heterozygote (CT) genotype existed in the two strains with low allele frequencies (0. 068 and 0.079 for Nyalawi and Mesairi respectively). Moreover, three mutations were identified in exon5 of the GH1 sequence including two silent mutations at positions 2230 (C>T) and 2291(A>C) and a third transition mutation at position 2258 (C/T) detected in the sequences of the two strains. In conclusion, the two strains were found to be genetically similar at target positions. The detected mutation at exon 5 of GH1 (2258 (C/T) should be validated.

Keywords

• nyalawi
• mesairi
• polymorphisms
• igf-1
• gh1