Restriction digests of the clone give the following sizes (kb): EcoRI/HindIII--3.1, 0.64; PstI--3.7; EcoRI--3.2, 0.64; HindIII--3.8; SmaI--3.8. The same locus was independently ascertained by Y. Nakamura. Studies of 3-generation Utah families suggest the numerous fragments homologous to this probe are inherited as haplotypes. This probe is a subclone of cosmid 2-30 from a human genomic library. Insert contains several copies of a 39 bp repeat. Variation in copy number may be basis for multiple alleles. TaqI reveals at least 50 fragments (from <1 to >50 kb), many of which are polymorphic. Each of 27 unrelated individuals tested showed distinct band pattern. Similar variation seen with HaeIII, MspI, PstI and PvuII. Can use the entire plasmid as a probe. Hybridizes with unusually high efficiency. |
