Definition. Sex-linked diseases are passed down through families through one of the X or Y chromosomes. X and Y are sex chromosomes. Dominant inheritance occurs when an abnormal gene from one parent causes disease even though the matching gene from the other parent is normal.The abnormal gene dominates.efinition. Sex-linked diseases are passed down through families through one of the X or Y chromosomes. X and Y are sex chromosomes. Dominant inheritance occurs when an abnormal gene from one parent causes disease even though the matching gene from the other parent is normal.
Savant syndrome is a rare syndrome in which people with poor mental development or brain injury possess extraordinary mental skills which are difficult to explain scientifically. Sometimes the talents of a savant may go unnoticed.he exact cause of a savant syndrome is not known. A lot of hypotheses have been proposed. Some researchers believe that there is damage to the left hemisphere of brain, which results in compensatory changes in the right side of brain.
Cauda equina syndrome. With cauda equina syndrome, nerves at the base of the spinal cord become compressed. This affects nerves important for messages to the legs, feet and pelvic organs. This is a serious condition which can cause lower back pain, numbness, paralysis and bowel or urine problems.hese are the most common causes of cauda equina syndrome: 1  A herniation (bulging) of a spinal disk in the lumbar area that presses on the nerves (the most common cause). 2  Narrowing of the spinal canal (stenosis).