The aim of this study was to investigate the presence and the distribution of O and D alleles of alpha s2-casein gene (CSN1S2) in goat populations raised in some provinces of Turkey by means of PCR-RFLP method. It was aimed to detect those animals carrying the CSN1S2(O) allele in order to be able to establish a goat population consisting of animals homozygous for this allele. A total of 420 blood samples were collected from goats raised in Sanliurfa (207), Kilis (111) and Siirt (102) provinces. From the blood samples DNA was isolated. The DNA region was amplified by means of PCR technique, cut by using the restriction enzyme NcoI and analysed by using agarose gel electrophoresis. No animal carrying the CSN1S2(O) and CSN1S2(D) alleles was found. The results suggested that these alleles were not found in the goat populations studied. (C) 2008 Elsevier B. V. All rights reserved.