Lysosomal storage diseases (LSDs) are known as
genetic disorders with an overall prevalence of 1 per 7700 live births.
Sphingolipidosis, which is a subgroup of LSDs, is resulted from mutations in the coding genes of specific
enzymes of
sphingolipid hydrolases. The current study aimed to provide additional knowledge on the genotype of
sphingolipidoses disease among Iranian patients affected by the disease. In this research, we studied 68 unrelated Iranian patients diagnosed with one kind of
sphingolipidoses from 2014 to 2019. Thereafter, genomic
DNA was isolated from their peripheral blood leukocytes samples in
EDTA in terms of the manufacturer's protocol. All the coding exons and exon-intron boundaries of the related genes were sequenced and then analyzed using the NCBI database. Finally, they were reviewed using some databases such as the Human Gene Mutation Database (HGMD) and ClinVar ( https://www.ncbi.nlm.nih.gov/clinva ). By studying 22 MLD patients, 18 different variations of the ARSA gene were found, one of which was new including, named as c.472 T > G p. (Cys158Gly). Out of 15
Sandhoff disease (SD) patients, 11 different variations of the HEXB gene were found. Correspondingly, the c.1083-2delA was not reported earlier. By investigating 21 Iranian patients with
Tay-Sachs disease (TSD), one new variant was found as c.622delG. The study of 10
Niemann-Pick disease A/B (NPDA/B (patients has led to the identification of 9 different SMPD1 gene variations, among which 3 variations were novel mutations. The results of the present study can be expanded to the genotypic spectrum of Iranian patients with MLD, SD, TSD, and
NPD diseases and also used to innovate more effective methods for the detection of genetic carriers as well as diagnosing and counseling of Iranian patients affected with these disorders.