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.
Causes. Today, the term flat back syndrome has been broadened to include any patient with a decrease in lumbar lordosis causing symptoms. As such, flat back syndrome can occur as a result of any condition that shortens the front portion of the spine, causing the patient to lean forward. Flat back syndrome may develop as the result of the following causes: Degenerative Disc Disease, Lumbar Post Laminectomy Syndrome, Compression Fractures, Ankylosing Spondylitis. Degenerative Disc Disease: For some patients, progressive degeneration of the intervertebral discs or the shock absorbers of the spine may lead to a loss of height in the front part of the spine. As discs degenerate the spine begins to lean forward and lumbar lordosis decreases.