Aim: The study investigated the genetic polymorphism of the kisspeptin (KiSS1) gene and its relationship with litter size in Cyprus and Iraqi black goats.

Materials and Methods: Blood samples (n=124) were collected from the two goat breeds reared at the Agricultural Research-Ruminant Research Station Breeding Station, Baghdad, Iraq. Genomic DNA was isolated using a DNA extraction kit. Polymerase chain reaction (PCR) was used to amplify the KiSS1 gene. All PCR products were sequenced and samples were used for further analysis using NCBI-Blast online on the exon 1 (595 bp) region of the KiSS1 gene.

Results: The results of this study revealed a significantly (P<0.05) larger litter size of the Cyprus goat breed than in the Iraqi black goats in the first and second parity. Three (893G/C, 973C/A, and 979T/G) substitutions relative to the KiSS1 gene reference sequence (GenBank ID: J × 047312.1, KC989928.1) were identified. Only the mutation g893G>C was identified as a single nucleotide polymorphism (SNP) associated with litter size. Furthermore, the average alleles in KiSS1 gene of both types of goats 0.567 and 0.3715 GG, were recorded. The genotyping at locus g893C>G was demonstrating domination of fecundity quality litter size, Both genotypes SNP of GC were classified at this marked region of KiSS1 gene.

Conclusion: The study concluded that the role of the KiSS1 gene in fecundity, revealing the status of this gene as an indicator in the assisted of caprine breeding selection.

Keywords: DNA sequence, goat, kisspeptin gene, litter size, polymorphism.