Analysis of the C4 genes in baleen whales using a human cDNA probe

We have used a human C4 cDNA probe to investigate the complement component C4 gene in four members of the family Balaenopteridae: fin whale (Balaenoptera physalus), sei whale (B. borealis), minke whale (B. acutorostrata), and bryde's whale (B. edeni). Restriction mapping of genomic DNA from the first three species suggests the presence of only one locus in these species, and also shows that the C4 genes in the three species are very similar. We have used 14 restriction endonucleases to investigate the restriction fragment length polymorphism (RFLP) of fin whales, 13 enzymes for sei whales, and 8 enzymes for the minke whale. No polymorphism was seen in DNA from the five minke whale samples, but Rsa I and Taq I restriction enzymes gave polymorphism in fin and sei whales whereas Hind III and Msp I restriction enzymes showed polymorphism in sei whales only. Only one bryde's whale sample was available for investigation. The study of DNA available from mother-fetus pairs from the two polymorphic species demonstrated a simple, two-allele transmission of RFLP alleles.