Neurological diseases in which there are defects in DNA repair or synthesis

摘要: This chapter discusses the clinical features and genetics of neurological diseases in which there are defects DNA repair or synthesis. There three disorders symptoms signs occur a defect synthesis has been clearly demonstrated. Two these—xeroderma pigmentosum ataxia telangiectasia—are also associated with an increased risk neoplasia, but third condition, Cockayne's syndrome is not. The earliest sign xeroderma appears first year life when sensitivity skin to sunlight leading erythema, edema, blistering. If possible, diagnosis should be made at this age, so that prophylactic measures may taken avoid subsequent sun-induced damage eyes. In telangiectasia, onset usually soon after infant starts walk, occasionally can delayed end decade. ataxic disturbance one posture gait later intention tremor dysarthria develop. essentially consists depressed growth between two years, both weight head circumference starting then fall away from previous normal centiles. Some patients display light skin.