All are true about chromosomal instability syndrome except-
DNA repair defect
Autosomal dominant inheritance
Increased risk of malignancy
Associated immunodeficiency
Ans. is 'b' i.e., Autosomal dominant inheritanceo Chromosomal instability syndromes are typically transmitted in an autosomal recessive mode of inheritanceChromosome instability syndromeso They are a group of inherited conditions associated with chromosomal instability and breakage. The disorders are characterized by a defect in DNA repair mechanisms or genomic instabilityo Susceptibility to exogenous genotoxic agents such as ultraviolet (UV) light, oxidative stress, and chemical mutagens, can also lead to a variety of nucleotide modifications and DNA strand breakso Patients with these disorders show increased predisposition to cancer.o Another hallmark of these disorders is immunodeficiency, a phenotype caused by an inability to properly repair DNA strand breaks that occur during development of the immune system,o Important chromosomal syndromes are1) Ataxia telangiectasia2) Ataxia telangiectasia-like disorder3) Bloom syndrome4) Fanconi anaemia5) Nijmegen breakage syndrome6) Xeroderma pigmentosum,7) Cockayne's syndrome
Cytogenetic Disorders