Genetic polymorphisms, causing variation in casein genes (CSN1S1, CSN1S2, CSN2, and CSN3), have been extensively studied in goats and cows, but there are only few studies reported in camels. Therefore, we aimed to identify alleles with functional roles in the United Arab Emirates dromedary camel (Camelus dromedarius) population to complement previous studies conducted on the same species. Using targeted next-generation sequencing, we sequenced all genes in the casein gene cluster in 93 female camels to identify and characterize novel gene variants. Most variants were found in noncoding introns and upstream sequences, but a few variants showed the possibility of functional impact. CSN2 was found to be most polymorphic, with total 91 different variants, followed by CSN1S1, CSN3 and CSN1S2. CSN1S1, CSN1S2 and CSN2 each had at least two variants while CSN3 had only one functional allele. In future research, the functional impact of these variants should be investigated further.
Keywords: CSN1S1; CSN1S2; CSN2 and CSN3; Casein; camel; casein genetic variability; dromedary; next generation DNA sequencing; the UAE.