HETEROGENEITY OF DNA AND RNA IN HUNTER PATIENTS

Genomic DNA and total RNA from lymphoblasts of nine unrelated Italian patients affected with Hunter syndrome were analyzed using a human cDN A clone coding for the lysosomal enzyme iduronate-2-sulphatase (IDS). Southern blot analysis resulted in patterns similar to the normal cont rol for seven of the patients analyzed; an aberrant pattern was observ ed in two patients (F.N. and P.D.), suggesting deletions/rearrangement in the IDS gene. Northern blot analysis showed in seven patients, a p attern similar to the normal control; for patients F.N. and P.D. the p attern was atypical, i.e., normal RNA species were absent whereas two different transcripts occurred. These data confirm the heterogeneity o f the molecular defects causing Hunter disease.