遗传学试题资料：Monogenic disorders

1、1.One characteristic of a mutation is that it is (4.0分)A.Almost an improvementB.Genetically transmitted to future generationsC.Always a dominant characteristicD.Prevented by using colchicine2.Contrasting genes at the same locus are called(4.0分) A.HomologusB.AllelesC.AlliesD.DifactorsE.Associates（等位基

2、因）3.某人的父亲为Huntington舞蹈病患者，他现已30岁还未发病，如果30岁时此病的外显率为30%，则他将来发病的可能性为（）。(4.0分)A.0%B.15%C.35%D.100%E.30%(患者的子代有1/2的概率患病，0.5*0.3=0.15，P78)4.Susan had retinoblastoma as a child. Her 1year-old daughter Cindy has just been found to have the same autosomal dominant condition. Susan is pregnant and concerned t

3、hat the new baby will also have retinoblastoma. Given that the penetrance of mutations in the causative gene, RB , is 90%, what is the risk that the baby will have this cancer?(4.0分)A.1%B.10%C.45%D.50%E.90%5.A 34-year-old woman presents to the emergency room with burning, stabbing, epigastric abdomi

4、nal pain. She reports nausea and vomiting over the past 24hours and states that she thinks that she may be pregnant. Urinalysis ispositive for ketones, WBCs, RBCs, and bacteria. Pregnancy test is positive. An abdominal CT reveals thromboses in the splenic, superior mesenteric, and left renal and por

5、tal veins. Further testing reveals a factor V Leiden mutation inone allele. There is no family history of thrombosis disorders in her family or her husbands family. Further analysis reveals a mutation in the mothers factor V Leiden gene; the father does not have the mutation. The patient is concerne

6、d about her pregnancy in light of these findings. What is the probability her child will be affected by factor V Leiden thrombophila?(4.0分)A.Virtually 0%B.25%C.50%D.75%E.100%（中英文版P160）6.多指症为常染色体显性遗传病，如果其外显率为60%，两个杂合型患者婚后所生子女表型正常的概率为（）。(4.0分)A.30%B.20%C.55%D.50%E.15%（1/2 *0.4+0.25=0.45）7.Huntington舞蹈

7、病患者重复扩增的三联体是（）。(4.0分) P79A.CAGB.GCGC.CTGD.GAAE.CGG8.父亲为A血型，母亲为B血型，生育了1个B血型的孩子，如再生育，孩子可能的血型为（）。(4.0分)A.A和BB.B和ABC.A、B和ABD.A和ABE.A、B、AB和O9.一个男孩是甲型血友病（XR）的患者，其父母和祖父母均正常，其亲属中不可能患此病的人是（）(4.0分)A.外祖父或舅父B.姨表兄弟C.姑姑D.同胞兄弟10.Your patient is a 5-year-old girl who appears to have Duchenne musculardystrophy. What

8、 is the most likely genetic explanation for this disease in a girl?(4.0分)A.She has a 46, XY karyotype with sex reversal.B.She has skewed X inactivation.C.She has two independentDMD mutations.D.She has a dominant negative mutation.E.This diagnosis is impossible.(XR,其中一条X染色体失活)11.Match the characteris

9、tics to the mode of inheritance.Elevated paternal age is characteristic(4.0分)A.Autosomal dominantB.Autosomal recessiveC.X-linked recessiveD.ChromosomalE.Polygenic（显性遗传病，父本年龄越高，突变率越大）12.Match the characteristics to the mode of inheritance.Parents with three affected children have a higher recurrence

10、risk than parents with two affected children(4.0分)A.Autosomal dominantB.Autosomal recessiveC.X-linked recessiveD.ChromosomalE.Polygenic(P113)13.Match the characteristics to the mode of inheritance.Elevated material age is characteristic(4.0分)A.Autosomal dominantB.Autosomal recessiveC.X-linked recess

11、iveD.ChromosomalE.Polygenic（母本年龄越高，越容易患染色体疾病）14.Match the characteristics to the mode of inheritance.When male-to-male transmission is observed, this mode is unlikely(4.0分)A.Autosomal dominantB.Autosomal recessiveC.X-linked recessiveD.ChromosomalE.Polygenic15.Phenylketonuria (PKU) is an autosomal re

12、cessive disease that causesseveremental retardation if it is undetected. Two normal parents are told by their state neonatal screening program that their third child has PKU. Assume the initial screening is accurate and answer the questions below.What is the risk for their next child to have PKU?(4.

13、0分)A.100 %B.67%C.50%D.25%E.Virtually 016.Match the descriptions below with the appropriate term. A 90-year-old man with autosomal dominant neurofibromatosis has a son and grandson who died in their twenties from neural tumors(4.0分)（P95）A.Genetic heterogeneity(表型一致，可能又不同的基因型遗传异质性)B.Variable expressiv

14、ity（表现度）C.Germinal mosaicism（生殖系嵌合体双亲表型正常，孩子却可能AD或XR）D.Nonrandom X inactivation（不随机的X染色体失活）E.Incomplete penetrance（不完全外显度）17.Match the descriptions below with the appropriate term.A albino couple has a normal child (albinism is an autosomal recessive disorder)(4.0分)A.Genetic heterogeneityB.Variable

15、expressivityC.Germinal mosaicismD.Nonrandom X iinactivationE.Incomplete penetrance18.Match the descriptions below with the appropriate term.A grandson and paternal grandfather have ectrodactyly ( autosomal dominant disorder with absent middle fingers), but the father has normal hands(4.0分)A.Genetic

16、heterogeneityB.Variable expressivityC.Germinal mosaicismD.Nonrandom X inactivationE.Incomplete penetrance19.Match the descriptions below with the appropriate term. A female carrier of hemophilia (X-linked disorder) has severe bleeding after routine cuts or abrasions(4.0分)A.Genetic heterogeneityB.Var

17、iable expressivityC.Germinal mosaicismD.Nonrandom X iinactivationE.Incomplete penetrance20.Which of the following prenatal diagnostic techniques routinely allows fetal chromosomes to be analyzed during first trimester of pregnancy?(4.0分)A.Cordocentesis（脐带穿刺术17-32周）B.Ammiocentesis (羊膜腔穿刺技术16-18周)C.Ch

18、orionic villus sampling（绒毛取材术，9-12周）D.Radiography（X线摄影术;）E.Maternal triple testing（母亲的三重测试）21.A young couple both affected with classical achondroplasia come to you for genetic counseling. There is no other family history of achondroplasia. You should inform them that if they have a tull term live b

19、orn, the probabi1ity that the newborn wi11 not have achondroplasia （软骨发育不全）if about:(4.0分)A.1%B.25%(老师给的答案)C.33%D.50%纯和胚胎致死,孩子都不出来。哪来的患病率！我去。22.Many biochemical defects, which are inherited in a single-gene Mendelianfashion, have multiple effects upon the individual affected. This phenomenon is know

20、n as:(4.0分)A.phenocopyingB.pleiotropy（基因多效性）C.incomplete penetranceD.codominance23.Thus far, two genes have been found that can cause autosomal dominant breast cancer (one on chromosome 13 and one on chromosome17). This is best described as an example of:(4.0分)A.LinkageB.Allelic heterogeneityC.Linka

21、ge disequilibriumD.Locus heterogeneity24.Mutt and Jeff are two brothers who were born with congenital deafness. Their parents had normal hearing. Mutt married Mabel. Mabel was also congenitally deaf and her parents had normal hearing. Mutt and Mabel had 10 children (5 boys and 5 girls) all of whom w

22、ere born congenitally deaf. Jeff married Jane. Jane is not related to Mabel. Jane was congenitally deaf although her parents had normal hearing. Janes sister, Myrna, was also congenitally deaf. Jeff and Jane had 10 children (5 boys and 5 girls) none of whom were congenitally deaf. The probable explanation of the above pedigree is that:(4.0分)A.there is a single genetic locus with at least 2 different abnormal recessive alleles (a and b) which will result in congenital deafness when homozygous as either recessive aa, ab or bb.B.there are at least 2 different gene