HLA-DRB1 and Parkinson disease: A deep sequencing study of HLA genes carried out to associate single nucleotide polymorphisms (SNP) with the risk of PD revealed genetic variant protection by valine at position 11 and a specific epitope at position 70–74 on the HLA-DRB1 molecule of HLA-DRB1*04:01, *04:04 and *04:05.