Analysis of genetic polymorphisms in the major histocompatibility complex of Japanese quail

The restriction fragment length polymorphisms (RFLP) of the Japanese quail MHC were assayed in seven lines using PvuII-digested DNA and a chicken Class II probe. The lines of Japanese quail surveyed included a randombred control population (R1) and sublines of R1 divergently selected for 4-wk body weight (HW and LW lines) or plasma yolk precursor as measured by total plasma phosphorus (TPP) (HP and LP lines). In addition, two sublines (HW-HP and HW-LP) of the HW line were included in the analysis. Males of both sublines were selected for increased 4-wk body weight whereas the females were selected for increased (HW-HP) or decreased (HW-LP) TPP. The number of birds surveyed per line ranged from 13 to 16. The chicken probe used produced discernible bands or fragments using Southern blot analysis. There were 16 different RFLP patterns as well as 7 different heterozygote patterns detected in the various Japanese quail lines. The band or fragment number of each pattern varied from 7 to 15. A total of 28 different bands or fragments were seen in the RFLP patterns and only 2 bands or fragments were common to all 16 patterns. The distribution of the RFLP patterns differed greatly among the Japanese quail lines. The R1 line differed in frequency of the patterns from all of the selected lines. The divergently selected lines (HW vs LW; HP vs LP; and HW-HP vs HW-LP) also differed in the frequency of the various RFLP patterns. In the comparison of the HW and LW lines, there were no RFLP patterns in common between the two lines. The results of the present study indicated that the Japanese quail MHC Class II genes were highly polymorphic.