8 Phenylketonuria (PKU) is one of the most common recessive genetic disorders in humans. Infants with PKU are missing an enzyme called phenylalanine hydroxylase, which is needed to break down an amino acid called phenylalanine. If a strict diet that minimizes the amount of phenylalanine in the diet is not followed, a severe nervous disorder may result. If two heterozygous parents (Pp) have a child, what is the possible genotype and phenotype for this individual? a. genotype of male b. genotype of female c. genotypes of offspring d. phenotypes of offspring

8 Phenylketonuria (PKU) is one of the most common recessive genetic disorders in humans. Infants with PKU are missing an enzyme called phenylalanine hydroxylase, which is needed to break down an amino acid called phenylalanine. If a strict diet that minimizes the amount of phenylalanine in the diet is not followed, a severe nervous disorder may result. If two heterozygous parents (Pp) have a child, what is the possible genotype and phenotype for this individual? a. genotype of male b. genotype of female c. genotypes of offspring d. phenotypes of offspring

Human Heredity: Principles and Issues (MindTap Course List)

11th Edition

ISBN:9781305251052

Author:Michael Cummings

Publisher:Michael Cummings

Chapter11: Genome Alterations: Mutation And Epigenetics

Section: Chapter Questions

Problem 16QP: Familial retinoblastoma, a rare autosomal dominant defect, arose in a large family that had no prior...

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Phenylketonuria (PKU) is an autosomal recessive disease that results from a defect in an enzyme that normally metabolizes the amino acid phenylalanine; when this enzyme is defective, high levels of phenylalanine cause brain damage, in the past, most children with PKU became intellectually disabled. Fortunately, intellectual disability can be prevented in these children by carefully controlling the amount of phenylalanine in the diet. The diet is usually applied during childhood when the brain development is taking place. As a result of this treatment, many people with PKU now reach reproductive age. Children born to women with PKU (who are no longer on a phenylalanine-restricted diet) frequently have low birth weight, developmental abnormalities, and intellectual disabilities. However, children of men with PKU do not have these problems. Describe the results depicted in Fg1. and us it to provide an explanation for these observations What type of genetic effect is…
Phenylketonuria (PKU) is an autosomal recessive disease that results from a defect in an enzyme that normally metabolizes the amino acid phenylalanine; when this enzyme is defective, high levels of phenylalanine cause brain damage, in the past, most children with PKU became intellectually disabled. Fortunately, intellectual disability can be prevented in these children by carefully controlling the amount of phenylalanine in the diet. The diet is usually applied during childhood when the brain development is taking place. As a result of this treatment, many people with PKU now reach reproductive age. Children born to women with PKU (who are no longer on a phenylalanine-restricted diet) frequently have low birth weight, developmental abnormalities, and intellectual disabilities. However, children of men with PKU do not have these problems. QUESTION: Describe the results depicted in Fig. 1 Use the first question to provide an explanation for these observations. What type of genetic…
1a) Explain how amino acids in casein could reach the liver, starting fromthe moment when the person takes a bite of pastry cream pie. b) Congenital lactase deficiency is a type of lactose intolerance that occursin infants. It is inherited in an autosomal recessive pattern. Calculate thechance of congenital lactose intolerance in a child whose parents are both carriersfor the disorder, showing fully how you reached your answer.
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Sickle-cell anemia is a recessive autosomal disorderthat is caused by an amino acid substitution in theβ-hemoglobin protein. The DNA mutation underlyingthis substitution is a SNP that alters a GAG codon forthe amino acid glutamate to a GTG that codes a valine.The frequency of sickle-cell anemia among AfricanAmericans is about 1/400. What is the frequency ofthis GTG codon in the β-hemoglobin gene amongAfrican Americans?
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Which of the following best explains how individuals who inherit phenylketonuria alleles can avoid the symptoms of this disease (mental impairment, foul smelling urine)?
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Bloom's Syndrome is an autosomal recessive disorder due to mutations in a helicase protein. Some of the consequences of this disease are higher frequency of cancer and a shortened lifespan. Which of the following properties would not be expected to be associated with this disorder? two carrier parents one carrier parent and one normal one
Canavan Disease Canavan disease in an autosomal recessive disorder caused by mutations in the gene that codes for the enzyme aspartoacylase resulting in incomplete synthesis of myelin sheaths. Individuals affected by Canavan disease experience lack of motor development, abnormal muscle tone, and difficulty feeding. Most individuals affected by this disease die before the age of 10. In a particular population in Canada, researchers examined 250 people for Canavan disease and found that 45 of them had the disorder. a) What is the frequency of Canavan disease in the population examined by the researchers? Show all your work. Express your answer as a value between 0 and 1 rounded to two decimal places. b) What is the frequency of the Canavan disease carriers in the population examined by the researchers? Show all your work. Express your answer as a value between 0 and 1 rounded to two decimal places.
Phenylketonuria and alkaptonuria are both autosomal recessive diseases. If a person with PKU marries a person with AKU, what will the phenotype of their children be?
Familial retinoblastoma, a rare autosomal dominant defect, arose in a large family that had no prior history of the disease. Consider the following pedigree (the darkly colored symbols represent affected individuals): a. Circle the individual(s) in which the mutation most likely occurred. b. Is the person who is the source of the mutation affected by retinoblastoma? Justify your answer. c. Assuming that the mutant allele is fully penetrant, what is the chance that an affected individual will have an affected child?