Medical Genetics

Las preguntas del cuestionario

1. 1. In a Robertsonian translocation fusion occurs at the:
   1. telomeres.
   2. centromeres.
   3. histones.
   4. ends of the long arms.
2. 2. Zinc finger proteins and helix-turn-helix proteins are
   1. types of DNA-binding proteins
   2. involved in the control of translation
   3. components of ribosomes
   4. part of the hemoglobin in blood cells
3. 3. If the frequency of males affected with an X-linked recessive condition in a human population is .10 (one in ten), what will be the expected frequency of affected females?
   1. 0.01
   2. 0.001
   3. 0.02
   4. 0.0001
4. 4. In DNA adenine normally pairs with:
   1. cytosine.
   2. guanine.
   3. thymine.
   4. uracil.
5. 5. The pattern of inheritance shown by malignant hyperthermia (hyperpyrexia) is:
   1. autosomal dominant.
   2. autosomal recessive.
   3. X-linked dominant.
   4. X-linked recessive.
6. 6. Mapping of human chromosomes:
   1. has been restricted to the sex chromosomes because of small family sizes
   2. proceeded much more successfully as large numbers of DNA markers became available.
   3. has determined that the number of linkage groups is about twice the number of chromosomes
   4. has demonstrated that almost all of the DNA is involved in coding for genes
7. 7. Intergenerational transmission to offspring can occur as a result of parental exposures to ______.
   1. war
   2. natural disasters
   3. hunger
   4. all of these
8. 8. Asp235Phe in a molecular report indicates that:
   1. asparagine has been replaced by phenylalanine.
   2. phenylalanine has been replaced by asparagine.
   3. aspartic acid has been replaced by phenylalanine.
   4. phenylalanine has been replaced by aspartic acid.
9. 9. The risk of abnormality in the child of a mother with untreated phenylketonuria is:
   1. 1%
   2. 10%
   3. 25%
   4. Almost 100%
10. 10. Exon skipping is associated with:
    1. nonsense mutations.
    2. regulatory mutations.
    3. RNA processing mutations.
    4. silent mutations.
11. 11. Which of the following is not a chromosome instability syndrome?
    1. Klinefelter syndrome
    2. Ataxia telangiectasia
    3. Fanconi anaemia
    4. Bloom syndrome
12. 12. Normal adult haemoglobin (Hb A) consists of:
    1. two α (alpha) and two β (beta) chains.
    2. two α and two γ (gamma) chains.
    3. two α and two δ (delta) chains.
    4. four γ chains.
13. 13. In a condition such as schizophrenia the recurrence risk will be greatest for which of the following relatives of an affected individual?
    1. Brother
    2. Nephew
    3. Grandchild
    4. Aunt
14. 14. The mutation in sickle-cell disease consists of:
    1. a deletion.
    2. a duplication.
    3. an insertion.
    4. a point mutation.
15. 15. Which of the following is an example of monosomy?
    1. 46,XX
    2. 47,XXX
    3. 69,XYY
    4. 45,X
16. 16. QTL analysis is used to
    1. identify chromosome regions associated with a complex trait in a genetic cross
    2. determine which genes are expressed at a developmental stage
    3. map genes in bacterial viruses
    4. identify RNA polymerase binding sites
17. 17. What would be the frequency of AABBCC individuals from a mating of two AaBbCc individuals?
    1. 1.0/64
    2. 1.0/32
    3. 1.0/128
    4. 1.0/256
18. 18. It is currently estimated that there are ______ human protein-coding genes although this estimate may be reduced over time.
    1. 10,000–15,000
    2. 19,000–20,000
    3. 29,000–30,000
    4. 100,000
19. 19. With which of the following relatives is an individual most likely to share a common HLA haplotype?
    1. Father
    2. Mother
    3. Sister
    4. Son
20. 20. Which of the following genes conveys susceptibility for polygenic Alzheimer disease?
    1. APP
    2. PS1
    3. PS2
    4. APOE
21. 21. The DiGeorge/Shprintzen syndrome is caused by a deletion in which chromosome?
    1. 4
    2. 7
    3. 15
    4. 22
22. 22. X-chromosome inactivation
    1. results in genetically turning off one of the two X chromosomes in female mammals
    2. takes place in humans so that the same X chromosome is inactive in all of the cells of a female
    3. is the cause of the Y chromosome being genetically inactive
    4. occurs in fruit flies but not in mammals
23. 23. The pattern of inheritance shown by glucose-6-phosphate dehydrogenase (G6PD) deficiency is:
    1. autosomal dominant.
    2. autosomal recessive.
    3. X-linked dominant.
    4. X-linked recessive.
24. 24. Homeobox sequences
    1. are present in the genome of many animal species
    2. are found in prokaryotes but not in eukaryotes
    3. were identified as the integration sites for bacterial viruses
    4. represent integration sites for transposable elements
25. 25. Which of the following karyotypes is diagnostic of Down syndrome
    1. 46,XX,der(14;21)(q10;q10)pat+21
    2. 47,XY,+13
    3. 45,XX,rob,(14;21)(q10;q10)
    4. 46,XY,t(2;3)(q21;q12)