![Genetic Analysis: An Integrated Approach (2nd Edition)](https://www.bartleby.com/isbn_cover_images/9780321948908/9780321948908_largeCoverImage.gif)
Concept explainers
Galactosemia is an autosomal recessive disorder caused by the inability to
(a) Draw a pedigree that includes Amanda, Brice, and their siblings and parents. Identify the genotype of each person, using G and g to represent the dominant and recessive alleles, respectively.
(b) What is the probability that Amanda is a carrier of the allele for galactosemia? What is the probability that Brice is a carrier? Explain your reasoning for each answer.
(c) What is the probability that the first child of Amanda and Brice will have galactosemia? Show your work.
(d) If the first child has galactosemia, what is the prob-ability that the second child will have galactosemia? Explain the reasoning for your answer.
![Check Mark](/static/check-mark.png)
Learn your wayIncludes step-by-step video
![Blurred answer](/static/blurred-answer.jpg)
Chapter 2 Solutions
Genetic Analysis: An Integrated Approach (2nd Edition)
Additional Science Textbook Solutions
Laboratory Experiments in Microbiology (12th Edition) (What's New in Microbiology)
Becker's World of the Cell (9th Edition)
Laboratory Experiments in Microbiology (11th Edition)
Campbell Essential Biology (7th Edition)
Brock Biology of Microorganisms (15th Edition)
- 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 Use the first question to provide an explanation for these observations. What type of genetic effect…arrow_forwardPhenylketonuria (PKU) is a human hereditary disease resulting from the inability of the body to process the chemical phenylalanine, which is contained in the protein we eat. PKU is manifest in early infancy and, if it remains untreated, generally leads to cognitive impairment. PKU is caused by a recessive allele with simple Mendelian inheritance. A couple intends to have children but consults a genetic counselor because the man has a sister with PKU and the woman has a brother with PKU. There are no other known cases in their families. They ask the genetic counselor to determine the probability that their first child will have PKU. What is this probability?arrow_forwardparents, but her brother Alonzo has Galactosemia. Brice has a similar family history. He and his parents are healthy, but his sister Brianna has galactose, a component of the lactose found in mammalian milk. Galactosemia can be galactosemia. Amanda and Brice are planning on marrying and starting a family and partially managed by eliminating dietary intake of lactose and galactose. Amanda is Galactosemia is an autosomal recessive disorder caused by the inability to metabolize seek genetic counseling. Based on the information provided, complete the following: healthy, as are her A piaw a pedigree that includes Amanda, Brice, their siblings, and parents. Identily the genotypes of each person using G and a to represent the dominant and recessive alleles. B What is the probability that Amanda is a carrier of the allele for galactosemia? Same question for Brice? Explain. non bard bito te over ovodaarrow_forward
- Achondroplasia is an autosomal dominant disorder characterized by disproportionate short stature: the legs and arms of people with achondroplasia are short compared with the head and trunk. The disorder is due to a base substitution in the gene, located on the short arm of chromosome 4, that encodes fibroblast growth factor receptor 3 (FGFR3). Although achondroplasia is clearly inherited as an autosomal dominant trait, more than 80% of the people who have achondroplasia are born to parents with normal stature. This high percentage indicates that most cases are caused by newly arising mutations; these cases (not inherited from an affected parent) are referred to as sporadic. Studies have demonstrated that sporadic cases of achondroplasia are almost always caused by mutations inherited from the father (paternal mutations). In addition, the occurrence of achondroplasia is higher among the children of older fathers; approximately 50% of children with achondroplasia are born to fathers…arrow_forwardSickle cell anemia is inherited as an autosomal recessive condition. It also exhibits incomplete dominance in that the heterozygous genotype displays a mild form of the disease known as sickle cell trait while individuals with the homozygous recessive genotype have a severe form of SCA. A man who has severe sickle cell anemia marries a woman who suffers from a mild trait. What is the probabilitu they will have a child with severe SCA?What is the probability they will have a child with mild SCA? What is the probability they will have a normal child? Show ALL work using punnett squares.arrow_forwardPancreatic cancer is clearly inherited as an autosomal dominant trait in the family illustrated in Figure 23.1. Yet most cases of pancreatic cancer are sporadic, appearing as isolated cases in families with no obvious inheritance. How can a trait be strongly inherited in one family and not inherited in another?arrow_forward
- One of your patients, a six-year-old girl who suffers from Sickle cell anemia, an inherited blood disorder in which red blood cells are abnormally shaped and fragile, leading to a short supply of red blood cells. These abnormal cells can also get stuck in small vessels, which prevent blood flow, leading to fatigue, pain and other severe complications. Sickle cell anemia is an autosomal recessive disorder. Neither of your patient's parents has sickle cell anemia. What is the most likely genotype of her parents? (The normal beta-globin allele is abbreviated as B, and the abnormal allele as b.) one is B and one is b one is BB and one is bb both are Bb both are bb both are BBarrow_forwardNiemann Pick Type C disease is a recessive disorder that causes the accumulation of cholesterol and other lipids in lysosomes, ultimately affecting both the liver and the nervous system. Below are the genotypes and phenotypes of offspring of a family with a history of Niemann Pick. 7 NN ( all normal phenotype) 3 Nn (all normal phenotype) 4 nn (1 early onset dementia, 1 mid-life onset dementia, 2 late-onset dementia). From this information, Niemann-Pick disease is an example of: A) variable expressivity B) incomplete dominance C) incomplete penetrance D) variable expressivity and incomplete penetrance E) multiple allelesarrow_forwardTuberous Sclerosis (TS) is an autosomal dominant genetic disease characterized by seizures, mental retardation, autism, and benign tumors of the brain, heart, skin, and kidneys. The kidney tumors can also be malignant. This disease exhibits a wide range of severity, and only about 1/3 of the cases are inherited. Two different genes have been tightly linked to the disease in families where it is inherited. The remaining 2/3 appear to be due to mutations in one of the 2 genes as well. Overall it appears that 1/2 are caused by mutations in TSC1 and the other half by mutations in TSC2. A rat model for hereditary renal carcinoma (kidney cancer) has been found. Southern and Northern blot analysis of the TSC1 and TSC2 gene revealed no differences between these rats and normal rats. Not all the rats in the strain would get cancer but a significant proportion did and those were selected for and used in experiments. 1. a) What was detected by the Southern blots? (look this up, make your…arrow_forward
- Salim and Sara are contemplating having children, but Salim’s brother has galactosemia and Sara has a sister who has three children, one of whom is affected. Sara dad has no history in his family of any sign of the diease and it is assumed to be homozygous normal. What is the probability that salim and saras first child will have galactosemia?arrow_forwardOlivia S. was born with a rare recessive disorder called tyrosinemia.The next day, Olivia M. was born in a neighboringstate with the same disorder. Tyrosinemia is causedby the lack of an enzyme in the degradation pathway of the aminoacid tyrosine. Accumulation of metabolic intermediates causesprogressive liver dysfunction and kidney problems. One-year-oldOlivia S. is healthy and has no symptoms of the disorder. At thesame age, Olivia M. developed total liver failure. Olivia S. was bornin a state where newborns are tested for tyrosinemia, but Olivia M.was born in a state where newborns are not tested for this disorder.A week after diagnosis, Olivia S. was placed on a low-tyrosinediet and prescribed a drug to block the accumulation of metabolicintermediates. Olivia M. was not diagnosed until she was in liverfailure; she then was placed on a low-tyrosine diet, was prescribedmedication, and underwent a liver transplant. She faces a lifetimeof antirejection drug therapy and may require a…arrow_forwardnbdayarrow_forward
- Human Heredity: Principles and Issues (MindTap Co...BiologyISBN:9781305251052Author:Michael CummingsPublisher:Cengage LearningBiology Today and Tomorrow without Physiology (Mi...BiologyISBN:9781305117396Author:Cecie Starr, Christine Evers, Lisa StarrPublisher:Cengage Learning
![Text book image](https://www.bartleby.com/isbn_cover_images/9781305251052/9781305251052_smallCoverImage.gif)
![Text book image](https://www.bartleby.com/isbn_cover_images/9781305117396/9781305117396_smallCoverImage.gif)