Detection of normal and HD huntingtin in human postmortem brain extracts
(A) Normal human brain. A Western blot of proteins extracted from dissected regions of a control human postmortem brain; temporal cortex (TC), frontal cortex (FC), and caudate and putamen (CP) were probed with 1:10,000 dilution of HF1. Preabsorption of the immune antiserum with HF1 fusion protein specifically eliminated the huntingtin band, and the additional bands were also detected by the preimmune serum (data not shown). The positions of the 200-kD marker (myosin) and of the huntingtin band are shown. (B) HD brain. A Western blot of proteins extracted from dissected regions of a grade 4 HD postmortem brain; cerebellum (Cb) and frontal cortex (FC) were probed with a 1:10,000 dilution of HF1. PCR analysis revealed that this individual carried a normal CAG allele of 18 repeat units and an expanded HD CAG allele of 41 repeats. The position of the 200-kD marker (myosin) is shown and the products of the normal and HD alleles, located close to each other at ∼350 kD, are denoted by a square bracket.