Ataxia Telangiectasia------>IgA deficiency
1.cereberal ataxia(narrow-based gate)
3.risk of sinopulmonary infections
Defect in the DNA break repair gene ATM (Ataxia Telangiectasia Mutant).
IgA deficiency-infections of the upper and lower airways.
ATM gene encodes a kinase essential for p53 activity. ATM is inactivated in ataxia telangiectasia-->hypersensitivity to x-rays and predisposition to lymphomas.