MHC CLASS-II B-GENE IN THE CHANNEL CATFISH (ICTALURUS-PUNCTATUS)

Two different cDNA sequences for major histocompatibility complex (MHC ) class II beta chains from the channel catfish (Ictalurus punctatus) have been identified. Homology between these sequences and those previ ously identified as MHC class II B genes in other teleosts suggests th ey represent alleles of the DAB locus. The inferred amino acid sequenc es show strong evidence for a functional polypeptide chain with a pept ide binding region. Southern blot analysis reveals polymorphism in the MHC class II B gene(s) of the channel catfish and suggests the presen ce of two to four genes. (C) 1997 Elsevier Science Ltd.