Polymorphic Ala-allele carriers at residue 1170 of HER2 associated with Parkinson's disease

HER2, a receptor tyrosine kinase, was originally identified based on its role in cancer research. The protein has subsequently received attention for its role in nerve injury and neurodevelopment. We investigated the polymorphic association of HER2 variants at amino acid residues 655 and 1170 with Parkinson's disease (PD), a neurodegenerative disorder.

Polymerase chain reaction (PCR) was used to amplify DNA samples from PD patients and control subjects. The resulting PCR fragments, which spanned HER2 residues 655 and 1170, were analyzed by restriction fragment length polymorphism and/or direct nucleotide sequencing.

The genetic distribution at residue 655 in PD patients did not differ from that in controls. However, homozygosity for genes encoding Pro at residue 1170 (Pro/Pro) occurred at a significantly lower rate among PD subjects. In other words, Ala-allele carries higher frequency in PD, especially among female PD subjects.

Different signals or potency of the kinase activities resulting from the Ala1170Pro allele of HER2 may be associated with vulnerability to stress on dopaminergic neurons in PD.