Context:

A team of doctors from Tamil Nadu along with scientists from Japan have developed a disease-modifying treatment for Duchenne Muscular Dystrophy (DMD).

About Duchenne Muscular Dystrophy(DMD):

• DMD  is a genetic disorder that is characterized by growing muscle degeneration and weakness. 
• Cause: It is caused due to the DMD gene failing to produce any functional dystrophin because of mutations in the dystrophin gene, found in the X chromosome.
• Onset: The onset of this genetic disorder is generally in early childhood, usually between the ages of two and three, and is typically known to affect boys.
• Diagnosis: A thorough clinical assessment, a complete review of the patient’s medical history along with a number of specialist testing, including genetic tests, are used to diagnose DMD.
• Treatment: Currently available treatments are gene therapy, exon-skipping and disease modifying agents (anti-inflammatory medicines such as steroids).

Why are Women affected rarely by DMD?

• Role of Mother: Women are usually carriers of the genetic trait and aren’t aware of carrying a mutation until they have an affected son. A carrier mother’s son has a 50 per cent possibility of inheriting the defective gene from her while the daughter of a carrier mother has a 50 percent chance of carrying the gene in two healthy copies and a 50 percent chance of becoming a carrier herself. 
• Role of Father: An unaffected father always either transmits a normal X to his daughter or a normal Y to his son whereas in an affected father it is an X-linked recessive disorder caused by a mutation in the dystrophin gene. 

News Source : The Hindu