duchenne muscular dystrophy is caused by a sex-linked recessive allele. its victims are almost invariably boys, who usually die before the age of 20. why is this disorder almost never seen in girls?

You which of the following statements is true? muscle tremors are an early symptoms of alzheimer's disease. type 2 diabetes is hereditary and cannot be prevented. certain medications can cure als and parkinson's disease. exercise is a natural way to relieve pain and stress.