Buffalo is the main source of white milk and contributes 45% of the annual milk production in Egypt. The STAT5A
protein has an important role in the signal transduction process within uterine epithelial cells and mammary glands affecting
milk yield, fertilization, and embryonic survival rates in cattle. The studies conducted for the improvement of the genetic
potentiality of productive and reproductive traits of Egyptian buffalo are still scanty. Data on polymorphisms of the buffaloes
STAT5A gene is limited. Hence, the present study aimed to identify novel polymorphisms in the STAT5A gene and to validate
its genotypic frequencies in Egyptian buffalo. A 929 bp including part of intron 7 to part of intron 9 and the intervening
exons of the STAT5A gene was amplified and genotyped by the SSCP method. Three different conformation patterns in the
investigated 60 buffaloes were observed. Pattern B showed the highest observed frequency of 51.7%, while patterns A and C
occurred at frequencies of 45% and 3.3% respectively. A Chi-square test showed that the Egyptian water buffalo population
was in Hardy-Weinberg equilibrium. STAT5A gene might be utilized as a potential molecular marker for effective animal
selection and breeding programs.