Bloom syndrome is an autosomal recessive disease that exhibitshaploinsufficiency. A recent survey showed that people heterozygousfor mutations at the BLM locus are at increased risk of colon cancer.Suppose you are a genetic counselor. A young woman is referred to youwhose mother has Bloom syndrome; the young woman’s father has nofamily history of Bloom syndrome. The young woman asks whether sheis likely to experience any other health problems associated with herfamily history of Bloom syndrome. What advice would you give her?

Bloom syndrome is an autosomal recessive disease that exhibitshaploinsufficiency. A recent survey showed that people heterozygousfor mutations at the BLM locus are at increased risk of colon cancer.Suppose you are a genetic counselor. A young woman is referred to youwhose mother has Bloom syndrome; the young woman’s father has nofamily history of Bloom syndrome. The young woman asks whether sheis likely to experience any other health problems associated with herfamily history of Bloom syndrome. What advice would you give her?

Name: Bloom syndrome is an autosomal recessive disease that exhibitshaploins
Uploaded: 2024-03-20T06:42:55.000Z
Channel: Bartleby
Description: Bloom syndrome is an autosomal recessive disease that exhibitshaploinsufficiency. A recent survey showed that people heterozygousfor mutations at the BLM locus are at increased risk of colon cancer.Suppose you are a genetic counselor. A young woman i

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...

See similar textbooks

Similar questions

In retinoblastoma, a mutation in one allele of the RB1 tumorsuppressorgene can be inherited from the germ line, causingan autosomal dominant predisposition to the developmentof eye tumors. To develop tumors, a somatic mutation in thesecond copy of the RB1 gene is necessary, indicating that themutation itself acts as a recessive trait. Given that the firstmutation can be inherited, in what ways can a second mutationalevent occur?
Six months pregnant, an expectant mother had a routineultrasound that showed that the limbs of the fetus wereunusually short. Her physician suspected that the babymight have a genetic form of dwarfism called achondroplasia,an autosomal dominant trait occurring with a frequency of about1 in 27,000 births. The parents were directed to a genetic counselorto discuss this diagnosis. In the conference, they learnedthat achondroplasia is caused by a mutant allele. Sometimes itis passed from one generation to another, but in 80 percent ofall cases it is the result of a spontaneous mutation that arisesin a gamete of one of the parents. They also learned that mostchildren with achondroplasia have normal intelligence and a normallife span. It has been suggested that prenatal genetic testing for achondroplasiabe made available and offered to all women. Wouldyou agree with this initiative? What ethical considerationswould you consider when evaluating the medical and societalconsequences of offering…
In individuals affected by cystic fibrosis, salt crystals may appear afterperspiration dries up. In addition, the disease causes respiratory disorderswhich can be both debilitating and lethal. It occurs in individuals homozygousfor the recessive gene. Two normal parents had a daughter with thesymptoms of this disease, and a normal son who marries a normal womanwith an afflicted A test (salt concentration in perspiration of heterozygotes ishigher than normal) disclosed that both are indeed carriers of the gene. If thefirst child born to the mating in (b) was defective, what is the probability thatthe 2nd child would also be defective?Express answer in fraction form
Six months pregnant, an expectant mother had a routineultrasound that showed that the limbs of the fetus wereunusually short. Her physician suspected that the babymight have a genetic form of dwarfism called achondroplasia,an autosomal dominant trait occurring with a frequency of about1 in 27,000 births. The parents were directed to a genetic counselorto discuss this diagnosis. In the conference, they learnedthat achondroplasia is caused by a mutant allele. Sometimes itis passed from one generation to another, but in 80 percent ofall cases it is the result of a spontaneous mutation that arisesin a gamete of one of the parents. They also learned that mostchildren with achondroplasia have normal intelligence and a normallife span. What information would be most relevant to concluding whichof the two mutation origins, inherited or new, most likelypertains in this case? How does this conclusion impact on thiscouple’s decision to have more children?
Ehler-Danlos syndrome is a rare disorder caused by a mutation ina gene that encodes a protein called collagen (type 3 A1). Collagenis found in the extracellular matrix that plays an important role inthe formation of skin, joints, and other connective tissues. Peoplewith Ehler-Danlos syndrome have extraordinarily flexible skin andvery loose joints. The following pedigree contains several individualsaffected with this syndrome, shown with black symbols. Basedon this pedigree, does the syndrome follow autosomal recessive,autosomal dominant, X-linked recessive, or X-linked dominantinheritance? Explain your reasoning.
Ehler-Danlos syndrome is a rare disorder caused by a mutation ina gene that encodes a protein called collagen (type 3 A1). Collagenis found in the extracellular matrix that plays an important role inthe formation of skin, joints, and other connective tissues. Peoplewith Ehler-Danlos syndrome have extraordinarily flexible skin and very loose joints. The pedigree below contains several individualsaffected with this syndrome, shown with black symbols. Based onthis pedigree, does the syndrome appear to follow autosomalrecessive, autosomal dominant, X-linked recessive, or X-linkeddominant inheritance? Explain your reasoning.
A boy with Klinefelter syndrome (47,XXY) is born to a motherwho is phenotypically normal and a father who has the X-linkedskin condition called anhidrotic ectodermal dysplasia. The mother’sskin is completely normal with no signs of the skin abnormality.In contrast, her son has patches of normal skin and patchesof abnormal skin. Question: Using the appropriate genetic terminology, describe themeiotic mistake that occurred. Be sure to indicate in whichdivision the mistake occurred.
Glucose-6-phosphate dehydrogenase deficiency/G6PDD (g) is an X-linked recessive conditionwherein the red blood cells of affected individuals undergo premature hemolysis. Fragile X syndrome(F), on the other hand, is an X-linked dominant mutation characterized by a mild to moderateintellectual disability. Amelogenesis imperfecta (A) is a congenital disorder affecting the formation ofthe teeth enamel making affected individuals at higher risk for dental cavities and related problems.Only male offspring inherit this condition. Jane is heterozygous for both X-linked traits like her mother. Her father is normal for both X-linked traits. James has a mother who suffers from G6PDD but not from fragile X-syndrome. His fatherdoes not exhibit any X-linked disorder but has amelogenesis imperfecta. A. What are the genotypes of the following: Jane: ______________________ James: ______________________Jane’s mother: _________________ James’ mother: ________________Jane’s father: __________________…
The maternal-effect mutation bicoid (bcd) is recessive. Inthe absence of the bicoid protein product, embryogenesis isnot completed. Consider a cross between a female heterozygousfor the bicoid mutation (bcd+/ bcd-) and a homozygousmale(bcd-/ bcd-). How is it possible for a male homozygous for the mutationto exist?
Diamond–Blackfan anemia (DBA) is a rare, dominantgenetic disorder characterized by bone marrow malfunction,birth defects, and a predisposition to certaincancers. Infants with DBA usually develop anemia in the firstyear of life, have lower than normal production of red blood cellsin their bone marrow, and have a high risk of developing leukemiaand bone cancer. At the molecular level, DBA is causedby mutations in any one of 10 genes that encode ribosomalproteins. The first-line therapy for DBA is steroid treatment,but more than half of affected children develop resistance tothe drugs and in these cases, treatment is halted. DBA can betreated successfully with bone marrow or stem cell transplantsfrom donors with closely matching immune system markers.Transplants from unrelated donors have significant levels ofcomplications and mortality. Given that a faulty ribosomal protein is the culprit and causesDBA, discuss the possible role of normal ribosomal proteins.Why might bone marrow cells be…
Diamond–Blackfan anemia (DBA) is a rare, dominantgenetic disorder characterized by bone marrow malfunction,birth defects, and a predisposition to certaincancers. Infants with DBA usually develop anemia in the firstyear of life, have lower than normal production of red blood cellsin their bone marrow, and have a high risk of developing leukemiaand bone cancer. At the molecular level, DBA is causedby mutations in any one of 10 genes that encode ribosomalproteins. The first-line therapy for DBA is steroid treatment,but more than half of affected children develop resistance tothe drugs and in these cases, treatment is halted. DBA can betreated successfully with bone marrow or stem cell transplantsfrom donors with closely matching immune system markers.Transplants from unrelated donors have significant levels ofcomplications and mortality. While a stem cell transplant from an unaffected donor is currentlythe only cure for DBA, genome-editing technologies mayone day enable the correction of…
A woman who sought genetic counseling is found to be heterozygousfor a chromosomal rearrangement between the second andthird chromosomes. Her chromosomes, compared to those in anormal karyotype, are diagrammed on the next page:(a) This woman is phenotypically normal. Does thissurprise you? Why or why not? Under what circumstancesmight you expect a phenotypic effect of such arearrangement?