Candidate gene analysis of SPARCL1 gene in patients with multiple sclerosis

Recently, proteomic analysis in cerebrospinal fluid (CSF) from patients with MS identified four proteins which are present in MS but not in normal human CSF, including SPARCL1, an extracellular matrix-associated protein member of the SPARC family. One hundred eighty-six patients with MS and 185 age-matched controls were genotyped for A/G single nucleotide polymorphism (SNP) in exon 1 (rs1049539), C/G SNP in exon 4 (rs1049544), resulting in a substitution of an aspartate with an histidine, and A/G substitution in the exon 5 (rs1130643), leading to the substitution of alanine with threonine. No significant differences in either allelic or genotypic frequency of the three SNPs were found (P>0.05), even in stratifying MS patients according to the course of the disease. Stratifying according to gender, a trend towards a decreased frequency of the C/C genotype of the rs1049544 was observed in male patients as compared with male controls (30.2% versus 44.0%; P=0.217). Despite proteomic studies in CSF from MS patients suggested an important role for SPARCL1 in the development of the disease, SPARCL1 gene does not appear to act as susceptibility factor for MS in the population investigated here. However, the frequency of the C/C genotype of rs1049544 was decreased in male patients, possibly conferring a lower risk of developing MS in male population. Further studies are needed to clarify this issue.