Scientists have found 29 new genetic variants linked to multiple sclerosis (MS) and say the findings should help drugmakers focus treatment research on precise areas of the immune system. In a study published in the journal Nature on Wednesday, researchers said the newly-found links point to the idea that T-cells -- a type of white blood cell responsible for mounting an immune response -- and chemicals called interleukins play a key role in the development of the debilitating disease, Reuters reported. Drugs in development that target the immune system include rituximab, sold under the brand name Rituxan by Roche and Biogen to fight leukemia, Tysabri from Biogen and Elan , Lemtrada, sold as Campath by Sanofi's unit Genzyme for cancer, and Abbott and Biogen's Zenapax or daclizumab. "We have implicated genes that are highly relevant to the actions of those drugs," said Alastair Compston of Cambridge University, who co-led the study. "It is now clear that multiple sclerosis is primarily an immunological disease. This is the way to nail this disease and get on top of it." Mid-stage trial data for daclizumab released on Tuesday showed the drug on a par with other new medicines for MS, but some of he side-effects were worrisome. Multiple sclerosis is one of the most common neurological conditions among young adults, affecting around 2.5 million people worldwide. It occurs when the protective coating, known as the myelin sheath, around nerve fibres in the brain and spinal cord begins to break down, slowing the brain's communication with the rest of the body. The affected pathways -- responsible for everyday activities such as seeing, walking, feeling, thinking and controlling the bowel and bladder -- lose the ability to function properly and are eventually destroyed. -- SPA
