Genetic Counseling

Females who are "carriers" for hemophilia:  a. Theoretically pass the allele for hemophilia to half of their offspring b. Theoretically pass the allele for hemophilia to half of their daughters who become at least "carriers" for this disorder c. All are correct d. Theoretically pass the allele for hemophilia to half of their sons who become hemophiliacs e. Usually do not show any symptoms of hemophilia

In order for a girl to inherit hemophilia A, her parents would have which genotypes?  a. XH XH, Xh Y b. XH Xh, XH Y c. XH XH, XH Y d. XH Xh, Xh Y e. Xh Xh, XH Y

Which of the following is a problem faced by scientists studying human genetics but not by scientists studying plant genetics? a. Inability to do controlled crosses b. Lack of interest from funding agencies c. Shared environment of parents and offspring d. The research is too costly

Which of the following are potential advantages of genetic testing for inherited diseases? a. individuals can make informed decisions about reproduction b. individuals have a greater sense of certainty about their own health c. any possible treatment can be started at an earlier age d. choices A & B only e. choices A, B and C

What is an important limitation of pedigree analysis in studying the inheritance many complex traits? a. many traits are not influenced by genes b. many traits are influenced by many loci c. many traits are influenced by the environment d. many traits are only found in some family members e. both b and c 

Use the pedigree diagram below to answer the following question. Blue toes is an autosomal recessive trait. What is the genotype of the female in generation I?

Consider this hypothetical pedigree for a sex-linked recessive trait.Can you say for certain what the genotype is for:a) the motherb) the daughter

Hemophelia is an X-Linked recessive trait. A woman who does not have hemophelia, has a father that does. If she has children with another man who does not have hemophelia, what is the chance (in a percent) that she has a child with the disease?

A healthy young couple are both carriers of cystic fibrosis, the chance that each of their future children will inherit this serious illness is:  a. 0%, because cystic fibrosis is not an inherited illness b. 25% c. 10% d. 50% e. 100%

A man with a type A blood marries a woman with type B blood. Their child has type O blood. What are the genotypes of these individuals? What other genotypes, and in what frequencies, would you expect in offspring from this marriage?

Recessive alleles seem to vanish in some generations and reappear in later generations because:  a. They cannot be expressed in males b. They are masked by a dominant allele c. They cannot be expressed in females d. They cannot be expressed in successive generations e. They are lost by mutation

The result of the following cross indicates that the genotype of the male parent is _____. (Using B as the wild type allele and b for the flat head allele)a. Bbb. Bc. BBd. be. bbIf B represents the allele for black eyes (dominant) and b represents the allele for orange eyes (recessive), what would be the phenotypic ratio of a cross between a homozygous black-eyed alien and an orange-eyed alien?(Express your answers using only the numbers with the dominant first and recessive second. For example: 3 black eyes : 1 orange eyes would be just 3:1)

To inherit an autosomal dominant disorder a person could receive the disease causing allele from:  a. The father only, not the mother b. The mother only, not the father c. The mother or the father d. The parent who does not exhibit the disease e. All are correct

To inherit an autosomal recessive disorder requires a person to receive the disease causing allele from:  a. The father only b. The mother only c. Only the parent having the disease d. Only one parent who is homozygous recessive for the disease e. Both parents

If a person has a recessive allele for a disease and that allele is masked by a normal dominant allele, this person:  a. Homozygous for the disease b. Cannot produce gametes c. Is termed a "carrier" d. Is termed a linkage group e. Has the disease but cannot pass this disease to their offspring

Diagrams depicting family relationships and phenotypes for a genetic disorder are:  a. Linkage maps b. Pedigree charts c. Karyotypes d. Punnett squares e. Bell-shaped curves

In pedigree charts, autosomal dominant disorders typically:  a. Appear only in males b. Appear only in females c. Appear in every generation d. Seem to disappear in one generation, only to reappear in the next generation e. Occur every third generation

In pedigree charts, autosomal recessive disorders typically:  a. Appear in every generation b. Appear only in males c. Appear only in females d. Seem to disappear in one generation, only to reappear in the next generation e. Occur every third generation

What is the genotype of a man who has freckles (dominant) and is color-blind, if his mother lacked freckles?A man with a widow’s peak, whose mother was color blind and whose father had a continuous hairline, is engaged to marry a woman whose color blind mother had a continuous hairline, and whose normal visioned father had a continuous hairline.a. what is the genotype of the young gentleman?b. What is the genotype of his fiancée?If the couple in the preceding problem marry and have a family, what are the chances of them having:a. A normal visioned child with a continuous hairline?b. A color blind child with a widow’s peak?c. A normal visioned daughter with a continuous hairline?d. A color blind son with a widow’s peak?

In humans, dark hair (B) is dominant over blondness (b), and color blindness (c) is a sex-linked recessive trait. A women has a blond brother, a blond mother, and a dark-haired father. Her brother and her parents have normal vision. She bears the following three children by her blond, normal-visioned husband:a dark-haired son with normal vision,a dark-haired daughter with normal vision, anda dark-haired color-blind soni) Make a pedigree of the entire family showing the probable genotypes of all individuals.ii) What is the probability that her next (fourth) child will be a color-blind boy?iii) If her fourth child is a boy, what is the probability that he will have dark hair?iv) What is the chance that her next four children will all be girls?

Research has shown that a particular eye defect is represented in a family pedigree as shown below:i) On the basis of this data, which of the following mechanisms of inheritance are POSSIBLE? autosomal dominant, autosomal recessive, sex-linked dominant, sex-linked recessive, Y-linked.ii) What is the most PROBABLE mechanism of inheritance?iii) What is the genotype of female A?iv) What is the genotype of male B?v) What is the probability that a child from marriage C will show this eye defect?

The following pedigree shows the presence of individuals bearing extra fingers and toes--exhibiting "polydactyly." Explain the genetic mechanism for the inheritance of this trait in the family.

Given the family history below for the inheritance of a skin abnormality in humans, what is the correct mechanism of inheritance for this abnormality?

The inheritance of a particular facial hair pattern in a given family is indicated below. Answer the following questions about this family tree.

Because you have some basic knowledge of genetics, a young woman (A, below) has come to you for help. She has a brother who has a disease, but her parents and all of her husband's family are normal. She has a two-year-old daughter who shows the disease of her brother. She is now pregnant and is fearful that the next child will also have the disease. Can you help her by answering the questions below?i) What is the probability that her second child will have the disease?ii) If the second child is a boy, what is the probability that he will have the disease?

In cystic fibrosis, two unaffected carriers can have a child with the disease. It is as common in boys as in girls. This disease is:  a. Autosomal dominant b. X-linked recessive c. Autosomal recessive d. X-linked dominant e. Pleiotropic

In Huntington disease, a child will typically only get the disease if one parent also has it. It is as common in boys as in girls. This disease is:  a. Autosomal recessive b. X-linked recessive c. X-linked dominant d. Autosomal dominant e. Pleiotropic

Hemophilia A is an X-linked recessive disorder. If a normal man marries a woman who is a carrier, what fraction of their sons will have hemophilia?  a. 50% b. 25% c. 0% d. 100% e. 75%

Hemophilia A is an X-linked recessive disorder. If a normal man marries a woman who is a carrier, what fraction of their daughters will have hemophilia?  a. 25% b. 50% c. 0% d. 100% e. 75%

Below is a pedigree chart illustrating the transmission of hemophilia in the royal family of England.  Evaluate the pedigree and determine how such is transmitted within this family. Does the transmission rate seem high or low in comparison to what you know about different forms of transmission, mutations, etc.?  

The individuals in the above pedigree that are dark have ‘blue’ coat color. How is it transmitted? Note that the blue coated individual in the second generation has three different mates.a) a dominant alleleb) recessive allelec) codominant alleled) multiple alleles

The pedigree in the figure shows the transmission of a trait in a particular family. Based on this pattern of transmission, the trait is most likely X-linked dominant.a. Trueb. False

Assume that in cats, a crooked tail is caused by an autosomal recessive allele. A male and female cat, each with normal tails, have previously had a litter of kittens in which some kittens had crooked tails. What is the probability that the same two parents will next produce two normal females or two males with crooked tails?a. 5/8b. 9/16c. 9/32d. 9/64e. 5/32

The pedigree above could be explained by an X-linked dominant inheritance pattern.a. Trueb. False

In one of Morgan’s experiments, he crossed his newly discovered white-eyed male with a red-eyed female. (Note that all of the females at that time were homozygous for red eyes because the allele for white eyes had not yet propagated through Morgan’s flies.) All of the F1 flies produced by this cross (both males and females) had red eyes.Next, Morgan crossed the red-eyed F1 males with the red-eyed F1 females to produce an F2 generation. The Punnett square below shows Morgan’s cross of the F1 males with the F1 females.Drag the labels to their appropriate locations to complete the Punnett square for Morgan’s F1 x F1 cross.Drag pink labels onto the pink targets to indicate the alleles carried by the gametes (sperm and egg).Drag blue labels onto the blue targets to indicate the possible genotypes of the offspring.Labels can be used once, more than once, or not at all.

If the shaded phenotype in the pedigree above is caused by an autosomal dominant allele, then what is the chance that individuals labeled 4 & 5 (in row II) will have an unafflicted (unshaded) daughter?a. 100%b. 25%c. 50%d. 75%e. it cannot be determined from the information provided

Which of the following is LEAST likely to be a health problem for someone with cystic fibrosis?a. nutritional deficienciesb. diabetesc. frequent infectionsd. obesityThe allele that causes cystic fibrosis is recessive. An individual who is heterozygous for cystic fibrosisa. is a carrier.b. cannot reproduce.c. will have children who are all carriers of cystic fibrosis.d. cannot have children with cystic fibrosis.Sophie has cystic fibrosis. If Sophie conceives a child, and the father neither has cystic fibrosis nor is a carrier, what are the chances that the child would have cystic fibrosis?a. 25%, because only one in four gametes will carry the bad geneb. 50%, because there is a 50% chance that Sophie will pass along the bad genec. 100%, because Sophie has the conditiond. 75%, because Sophie has the condition but the father does note. 0%, because the child must receive the bad gene from both parentsSophie's parents are carriers for cystic fibrosis. If Sophie has a brother or sister from the same parents, what are the chances that the sibling would have cystic fibrosis?a. 50%b. 100%c. 75%d. 25%e. 0%

How is the trait shown by the dark squares being inherited?a. dominant (autosomal) b. recessive (autosomal) c. X-linked recessived. X-linked dominant  

Consider the following family history: A man with a widow's peak and normal color vision marries a color-blind woman with a straight hairline. The man's father had a straight hairline, as did both of the woman's parents. Use the family history to make predictions about the couple's children. Choose the correct label to the appropriate location in the table.  Not all labels will be used. 

A man has extra digits (six fingers on each hand and six toes on each foot). His wife and their daughter have a normal number of digits. Having extra digits is a dominant trait. The couple's second child has extra digits. What is the probability that their next (third) child will have extra digits?a. 9/16b. 3/4c. 1/16d. 1/2e. 1/8