Survey of major histocompatibility complex class II haplotypes in four turkey lines using restriction fragment length...

Four turkey lines were typed for MHC Class II haplotypes with restriction fragment length polymorphism (RFLP) analysis using a nonradioactive probe made from a chicken genomic clone of MHC Class II genes. The RFLP analysis detected 18 new patterns in the populations. There were three new haplotypes that had a frequency of about 10% or more in a population, whereas the rest appeared only once. The haplotype frequencies were significantly different in the E line, selected only for increased egg production, and the F line, selected only for increased body weight, compared with their respective randombred control lines. The shift of haplotype frequencies in the two selected lines seemed to be in opposite directions. One, but not the same, haplotype predominated in the selected lines, with about 50% of total haplotypes. Fewer haplotypes were frequent in the selected lines, whereas the frequencies in the control lines were relatively widely distributed, with the most frequent haplotype being below 35%. The frequency of homozygotes of the Class II haplotypes was the highest in the F line.