Genetic analysis of the glucocerebrosidase gene in South Indian patients with Parkinson's disease.

Background: Mutations in the glucocerebrosidase (GBA) gene have been associated with Parkinson's disease (PD). Several variants in the gene have been identified as risk factors for the development of PD, but there is difference in the prevalence of this mutation in various ethnic groups and countries. There is no published study related to this field on the Indian population.

Aims and Objectives: The aim of the study was to investigate the frequency of mutations in the GBA gene in Indian patients with PD.

Materials and Methods: To perform the mutation analysis of the GBA gene, we amplified its entire coding region, spanning 11 exons and intron/exon junctions in three fragments, with a set of three primer pairs using the long polymerase chain reaction enzyme mix from Fermentas, Canada.

Results: We screened a total of 100 PD patients for mutations in the GBA gene. The sequence analysis identified the following five variants in this gene: IVS1 + 191G > C, IVS4 + 47G > A (rs. 2075569), IVS6 - 86A > G (rs. 114099990), IVS9 + 141A > G (rs. 28373017), and IVS10 + 3G > A. Of these, two variants IVS1 + 191G > C and IVS10 + 3G > A are novel, and the remaining three are known variants reported in the Single Nucleotide Polymorphism database (dbSNP). All the known variants were detected in homozygous as well as in heterozygous states. Both novel variants were identified in only one patient in a heterozygous state.

Conclusion: GBA mutation may not be so common in Indian patients with PD as compared to the other ethnic populations. These findings need to be confirmed in larger studies.