Differences in the number of embryonic and pseudo-beta-globin genes between HbA and HbB sheep

DNA samples obtained from 8 goats, 1 moufflon, and 84 sheep with HbA, HbAB, and HbB belonging to different breeds were digested with BamHI, EcoRI, HindIII and PstI and probed with the 5' end of the goat epsilon IV- and psi beta Z-globin genes. Sheep homozygous for HbA show a different restriction pattern than sheep homozygous fo HbB with each of these endonucleases. The main difference is that HbB sheep lack the epsilon II and psi beta X genes. These results, in addition to those previously obtained using a probe specific for beta-globin genes, suggest that HbB sheep probably lack the preadult four-gene set. The DNAs from moufflon and sheep homozygous for HbA show indistinguishable restriction patterns. Furthermore, a number of restriction fragment length polymorphisms (RFLPs) are detected in the epsilon IV and psi beta Z DNA regions, and one HindIII RFLP in the epsilon VI DNA region.