Characterization of three new deletions at the 5' end of the HPRT structural gene

In a panel of seven unrelated HPRT-deficient patients three partial deletions of the 5' end of the HPRT structural gene were identified by Southern blot analysis. The deletions could be defined as the loss of exons 1-3, exons 2-3 and exon 3 respectively. In two of the deletion mutations aberrant restriction fragments occurred.