The following diseases have defect in DNA repair mechanism except for -
Xeroderma Pigmentosa
Fanconi syndrome
Huntington's disease
Hereditary non polyposis colon cancer
Ans. is 'c' i.e., Huntington's disease Several genetic disorders have defective DNA repair capability due to involvement of DNA repair enzymes. o Mutation caused by defects in DNA repair accumulate as somatic cells divide these type of mutation can cause neoplastic growth. So, all these disorders have significantly increased risk of cancer. o Inherited autosomal recessive syndromes of defective DNA repair Ataxia Telangiectasia Fanconia anemia Hereditary Nonpolyposis cancer (Only Bloom syndrome Xeroderma pi gmentosum autosomal dominant) o These disorders are associated with such a high level of chromosomal instability that they are known as chromosome - breakage syndrome.