This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: None, Subject name: Pediatrics
[{'content': 'An affected male infant born to normal parents could be an example of all of the following, except - \nSelect and explain. \nA. An Autosomal dominant disorder, B. An Autosomal recessive disorder, C. A polygenic disorder, D. A veically transmitted disorder', 'role': 'user'}, {'content': "Answer: A \nExplanation: Ans. is 'a' i.e., Autosomal dominant disorder In Autosomal dominant disorders individuals are affected in successive generations. The disease does not occur in the offspring of unaffected individuals' ? Autosomal dominant o If both parents are normal, the disease cannot be autosomal dominant because it is manifested in Heterozygous state, So, even a single gene affection amongst the allel will cause the disease to be manifested. To be normal, a person should have normal copy of both allel. If both parents are normal, that means there is no abnormal gene. Autosomal recessive o In autosomal recessive disorder, if both parents are carrier (phenotypically normal) 25% of child will develop disease. Polygenic disorder o A trait is called `polygenic' if multiple genes on thought to contribute to the phenotype. o Polygenic disorders include Hypeension Diabetes, Asthma o A male infant with asthma or diabetes may will be born to normal parents Veically transmitted disorder o Passage of disease causing agent (pathogen) `veically' from mother to baby during the perinatal period is called 'veical transmission'. o A veically transmitted agent might lie dormant in the mother and not manifest in her clinically (normal mother) but may manifest in the child.", 'role': 'assistant'}]