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Pseudohypertrophic muscular dystrophy is an inherited disorder that causes gradual deterioration of the muscles. It is seen almost exclusively in boys born to apparently unaffected parents and usually results in death in the early teens. Is this disorder caused by a dominant or a recessive allele? Is its inheritance sex-linked or autosomal? How do you know? Explain why this disorder is almost never seen in girls.
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- Faulty Tooth Enamel Formation Amelogenesis imperfecta (AI) is a disorder of faulty tooth enamel formation. It is inherited in an autosomal dominant and X-linked dominant pattern. The expression of AI disorder is determined by mutations in the autosomal alleles. One copy of the mutated allele (A) will cause the disorder. The severity of the disorder is determined by mutations in a gene carried on the X chromosome. Normal (or non-severe) abnormality (XN) is dominant over the abnormality (or severe) (Xn) allele. In the absence of the autosomal dominant allele, the abnormality gene on the X chromosome is notexpressed. Question:A woman with normal teeth had four children with a man with non-severe form of AI: A boy was born without amelogenesis imperfecta A girl was born without amelogenesis imperfecta A boy was born with severe amelogenesis imperfecta A boy was born with non severe amelogenesis imperfecta Identify the parental genotypes. Complete the Punnett square for the parental…arrow_forwardAlbinism is an autosomal recessive disorder. If a non-carrier normal male mates with an albino female, what percentage of their children will be albino? What percentage of their offspring will be normal, but carriers for the condition?arrow_forwardPenile hypospadias, a birth defect in male humans in which the urethra opens on the shaft instead of at the tip of the penis, results from an autosomal dominant gene in some families. Females who carry the gene show no effects. What type of trait is this birth defect an example of? a sex-limited trait because the defect occurs only in males and the gene involved is autosomal a Y-linked trait because the defect occurs only in males a genetic maternal effect because the presence of the trait depends upon the genotype of the mother an X-linked trait because the defect occurs more often in males than in females a sex-influenced trait because the defect occurs only in males and the gene involved is autosomalarrow_forward
- Two affected daughters and two normal sons are born to an affected male and a normal female. Each of the affected daughters (and their normal husbands) gave birth to affected sons and daughters. Normal sons of the couple married normal women and had normal children. Which of the following is the most likely mode of inheritance for this trait?* Sex-linked recessive Sex-linked dominant Autosomal dominant Autosomal recessivearrow_forwardAmelogenesis imperfecta (AI) is a disorder of faulty tooth enamel formation. It is inherited in an autosomal dominant and X-linked dominant pattern. The expression of AI disorder is determined by mutations in the autosomal alleles. One copy of the mutated allele (A) will cause the disorder. The severity of the disorder is determined by mutations in a gene carried on the X chromosome. Normal (or non-severe) abnormality (XN) is dominant over the abnormality (or severe) (Xn) allele. In the absence of the autosomal dominant allele, the abnormality gene on the X chromosome is not expressed. Question:A woman with normal teeth had four children with a man with non-severe form of AI: A boy was born without amelogenesis imperfecta A girl was born without amelogenesis imperfecta A boy was born with severe amelogenesis imperfecta A boy was born with non severe amelogenesis imperfecta Identify the parental genotypes. Complete the Punnett square for the parental cross, and identify the…arrow_forwardAmelogenesis imperfecta (AI) is a disorder of faulty tooth enamel formation. It is inherited in an autosomal dominant and X-linked dominant pattern. The expression of AI disorder is determined by mutations in the autosomal alleles. One copy of the mutated allele (A) will cause the disorder. The severity of the disorder is determined by mutations in a gene carried on the X chromosome. Normal (or non-severe) abnormality (XN) is dominant over the abnormality (or severe) (Xn) allele. In the absence of the autosomal dominant allele, the abnormality gene on the X chromosome is notexpressed. Question:A woman with normal teeth had four children with a man with non-severe form of AI: A boy was born without amelogenesis imperfecta A girl was born without amelogenesis imperfecta A boy was born with severe amelogenesis imperfecta A boy was born with non severe amelogenesis imperfecta Identify the parental genotypes. Complete the Punnett square for the parental cross, and identify the possible…arrow_forward
- Amelogenesis imperfecta (AI) is a disorder of faulty tooth enamel formation. It is inherited in an autosomal dominant and X-linked dominant pattern. The expression of AI disorder is determined by mutations in the autosomal alleles. One copy of the mutated allele (A) will cause the disorder. The severity of the disorder is determined by mutations in a gene carried on the X chromosome. Normal (or non-severe) abnormality (XN) is dominant over the abnormality (or severe) (Xn) allele. In the absence of the autosomal dominant allele, the abnormality gene on the X chromosome is not expressed. Question:A woman with normal teeth had four children with a man with non-severe form of AI: A boy was born without amelogenesis imperfecta A girl was born without amelogenesis imperfecta A boy was born with severe amelogenesis imperfecta A boy was born with non severe amelogenesis imperfecta Identify the parental genotypes. Complete the Punnett square for the parental cross, and identify the…arrow_forwardUse these two pictures to answer all the questions completely and correctly.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_forward
- Tuberous 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_forwardAchondroplasia 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_forwardPompe disease is a glycogen storage disorder caused by a lack of ⍺-glucosidase, the enzyme that converts glycogen to glucose in the muscles. Babies born with this disorder die by the age of two. Pompe disease is a genetic disorder caused by the presence of two recessive autosomal alleles. A man and a woman heterozygous for the condition have two female unaffected children. Determine the probability, expressed as a whole number percentage, of a third baby being born a male with Pompe disease. Your answer must include the use of a Punnett square as well as a legend indicating the allele symbols used. (2 marks)arrow_forward
- Biology (MindTap Course List)BiologyISBN:9781337392938Author:Eldra Solomon, Charles Martin, Diana W. Martin, Linda R. BergPublisher:Cengage Learning