The immunoglobulin heavy chain variable region (Igh‐V) locus in the mouse. I. One hundred Igh‐V genes comprise seven families of homologous genes

TLDR

Southern blot analysis of genomic DNA from eighteen inbred mouse strains defined seven families of Igh‑V genes, with twenty‑four cloned Vh genes hybridizing to one of seven nonoverlapping Eco RI fragment sets. The locus comprises roughly one hundred Vh genes, with families containing 2 to ~40 fragments, intra‑family homology >80% and inter‑family <70%, and extensive restriction fragment length polymorphism allowing complete Igh haplotype assignment for the eighteen strains.

Abstract

Seven families of Igh-V genes have been defined by Southern blot analysis of genomic DNA from eighteen inbred strains of mice. Each of twenty-four cloned Vh genes hybridized to one of seven nonoverlapping sets of Eco RI restriction fragments. These families contain from 2 to approximately 40 hybridizing fragments. From these data we estimate that the mouse Igh-V locus consists of one hundred Vh genes. Genes within a Vh family share greater than 80% sequence homology while the sequence homology between families is generally less than 70%. There is extensive restriction fragment length polymorphism among the strains analyzed allowing the assignment of complete (Igh-V + Igh-C) Igh haplotypes for eighteen inbred mouse strains.