Concept explainers
a.
To list: The genotypes of the family members.
Introduction: The dominant characters in the genotypes are represented by “PP”. Recessive characters are represented by letter “pp”. However, the heterozygous characters are represented by the “Pp”. The outsiders are also considered healthy and dominant and unknown genotypes are represented by P.
b.
To determine: The probability of the first child to have the PKU, when person A and B marry.
Introduction: Phenylketonuria is an autosomal recessive condition which is caused due to alteration of metabolic amino acid. The
c.
To determine: The probability of the second child to be unaffected when first child is diseased.
Introduction: Generally, a child to be diseased requires both the parents to be factor causing the disease. It is not necessary that parents will exhibit the signs, but without showing signs, parents can transmit the disease to progenies. The parents of the children can either be diseased or carrier.
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ACHIEVE:INTRO TO GENETIC ANALYSIS 1TERM
- The condition phenylketonuria is caused by a recessive allele. There are two carriers who have progeny.a. Give the gene notation. b. Give the expected genotypic and phenotypic ratios. c. What is the probability that their child will be heterozygous if they have a normal child?d. What is the probability of having two affected children and one normal child if they have three children?arrow_forwardA heterozygous individual is crossed with a homozygous recessive individual. a. Draw a Punnett square to represent this cross. b. What is the probability that an offspring will have a homozygous genotype? c. What is the probability that an offspring will have a dominant phenotype? d. What is the probability that three offspring will be produced that all carry the recessive allele but do not express the recessive phenotype?arrow_forwardColor blindness in humans is controlled by an X-linked completely recessive allele (Xc), while breast cancer is controlled by an autosomal completely dominant allele, B. A color blind male, who is a heterozygote carrier for breast cancer has three children/n with a normal eyed female (whose mother was color blind), who is homozygote recessive for the breast cancer allele. What is the probability that out of three children, 2 will be color blind males, and not show breast cancer, and one will be a color blind female, who shows breast cancer?arrow_forward
- a. Determine if the pedigree below can be for a trait that is X-linked traits. Write the genotype of each individual next to the symbol. b. Is it possible that this pedigree is for an X-linked recessive trait? c. What can you conclude about the children if both parents are affected with an X-linked recessive trait?arrow_forwardDuchenne muscular dystrophy is sex linked and usually affects only males. Victims of the disease become progressively weaker, starting early in life.a. What is the probability that a woman whose brother has Duchenne’s disease will have an affected child?b. If your mother’s brother (your uncle) had Duchenne’s disease, what is the probability that you have received the allele?c. If your father’s brother had the disease, what is the probability that you have received the allele?arrow_forwardConsider a cross between a Brown furred dog and a Yellow furred dog. All the puppies born from these parents are yellow furred. Crossing the F1 yellow furred sons and F1 yellow furred daughters produces a 3:1 ratio of yellow furred dogs (3) to brown-furred dogs (1) in the F2 generation. True or False: this tells you that brown fur color in this dog species is inherited in an autosomal recessive manner. is it true or false?arrow_forward
- 15. The following pedigree shows inheritance of Huntington's disease, a fatal genetic disorder that causes neurodegeneration. Since signs and symptoms usually do not appear until adulthood, many who are carriers may not realize their risk of passing on the disease-causing allele. The following pedigree represents a family in which some people are affected by Huntington's disease. Reeessive Trit er btmnt be Mec yplicalty Hinheteearrow_forwardTrait W is found in the individuals represented by the shaded symbols in the following pedigree. Trait W is rare in the general population.Which of the following patterns of transmission is consistent with this pedigree? Select one: a. Autosomal recessive b. X-linked dominant c. X-linked recessive d. Autosomal dominantarrow_forwardThe chart below is showing 4 generations of a family that is affected by a hereditary disease. a. Is the disorder being tracked dominant or recessive? How do you know? b. There is only one possible genotype for person C. True or False? c. What are the possible genotypes for person A? d. What are the possible genotypes for person B?, e. If two people with the same genotypes as person C's spouse and person A's spouse had a child, what is the probability that the child will be affected by this genetic disorder? (draw a Punnett square using the correct genotypes to help you). % chance offspring will be affected % chance offspring will not be affectedarrow_forward
- Consider a situation where you have a parental cross with the mother and father phenotypes listed below. Remember that the genotype for the wild-type parent is always homozygous. The counts of the F1 offspring are listed in Table 1. Two randomly selected individuals are selected and mated to produce a set of F2 individuals. If you test the F2 counts to determine whether they are consistent with an autosomal dominant mode of inheritance, what is your decision? Use a 0.05 significance level. PARENTAL CROSS Parental cross: Mother with disease phenotype, Father with wild-type phenotype. Table 1. F1 DATA Gender Phenotype Disease Wild-type Male 0 23 Female 0 34 Table 2. F2 DATA Gender Phenotype Disease Wild-type Male 7 25 Female 0 25 A)Do not reject the null hypothesis that the F2 data are consistent with an autosomal dominant mode of inheritance; chi-square goodness of fit test statistic value is between 0 and 1. B)Reject the null…arrow_forwardSickle cell anemia is an inherited red blood cell disorder in which there are not enough healthy red blood cells to carry oxygen throughout the body. The allele that causes sickle-cell anemia is autosomal recessive (s), and the dominant allele can be represented by S. How many offspring will be affected by the disorder if the mother is a carrier, and the father appears to be normal? (Include the gender) a. b. How many will become carriers? (include the gender) A- 三三三 四 四 II !!arrow_forwardIn humans, the genetic disease cystic fibrosis is caused by a recessive allele (a). The normal (healthy) allele is dominant (A). What is the genotype of someone who has cystic fibrosis? What are the two different genotypes that a healthy person could have? If two people were both heterozygous for the cystic fibrosis gene, what fraction of their children would be likely to have this disease? Hint: Draw a Punnett square to figure it out.arrow_forward
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