Ataxia telangiectasia is characterised by all of the following except –

"Persistence of very high levels of oncofetal proteins, including alpha-fetoproteins and carcinoembryonic antigens is of diagnostic value" - Harrison Ataxia telangiectasia Ataxia Telangiectasia (AT) is an autosomal recessive disorder. It is due to mutation of AT gene located on chromosome 11. There is defective DNA repair that results in multiple chromosomal breaks. Clinical manifestations Present in the first decade of life. Feature are : - Oculocutaneous telengiectasia Neurological → Ataxia, dysarthria, extensor plantar response, myoclonic jerks, are flexia, distal sensory deficit. Immunodeficiency →Thymic hypoplasia with cellular and humoral (IgA and IgG2) immunodeficiency. Recurrent pulmonary infections Endocrine disorders → Type I DM Premature ageing Malignancies → Lymphoma, Hodgkin's disease, acute T cell leukemia, breast cancer. α-feto protein and carcino-embryonic antigen are increased