In our patient group, serum IGF-1 levels were significantly low in patients with primary progressive MS and those with high EDSS ≥ 6 and with disease duration > 5 years also; IGF-1 showed a significant negative correlation with EDSS, disease duration, and number of attacks suggesting the presence of correlation of serum IGF-1 levels and accumulation of disability in MS. The gene discussed is IGF1; the disease is primary progressive multiple sclerosis.