A 23-year-old asymptomatic male participates in clinical research and is found to be homozygous for the apolipoprotein E-4 allele. In the future, this patient is most likely to suffer from which of the following?

Question

A 23-year-old asymptomatic male participates in clinical research and is found to be homozygous for the apolipoprotein E-4 allele.  In the future, this patient is most likely to suffer from which of the following?

Quizplus · Accepted Answer

Alzheimer disease has a strong genetic predisposition. About 30% of patients have a family history of the disease. According to age when symptoms begin, Alzheimer disease can be classified as early or late. The following three mutation sites have been associated with early-onset familial Alzheimer disease (onset <60 years old): Both APP and presenilin gene mutations are thought to promote the production of A β-amyloid. Late-onset familial Alzheimer disease is associated with the ε4 allele of Apolipoprotein E. The exact mechanism of its influence is not known. It is thought that the ApoE4 protein may be involved in the formation of senile plaques. (Choice A) Familial hypercholesterolemia is an autosomal dominant disorder. It is associated with a defect in low-density lipoprotein (LDL) receptors. This defect leads to decreased hepatic LDL uptake and severe elevation in total cholesterol and LDL levels. (Choice B) Hypertrophic cardiomyopathy is a familial disorder inherited as an autosomal dominant trait. The most common mutation is of the β-myosin heavy chain. (Choice C) Genetic factors play an important role in diabetes mellitus type 2 (more important than in type 1). Genetic predisposition to increased insulin resistance and deranged insulin secretion by β-cells are important precursors to disease. (Choice D) Peptic ulcer disease is strongly associated with H. pylori infection, but not ApoE4. (Choice E) Polycystic kidney disease can be inherited as autosomal recessive (also called infantile form) or dominant trait (adult form). Neither of these conditions is associated with ApoE4. Educational Objective: Early-onset familial Alzheimer disease is associated with three gene mutations: APP (chromosome 21), presenilin 1 and presenilin 2. Late-onset familial Alzheimer disease is associated with apolipoprotein E4 genotype.

A 23-Year-Old Asymptomatic Male Participates in Clinical Research and Is