BRS Embryo Multifactorial Inherited Diseases - Numerical Chromosomal Anomalies

1. Which of the following aneuploidy situations describes the Turner syndrome?

Trisomy 13

Trisomy 18

Trisomy 21

(47,XXY)

(45,X)

Turner syndrome is a monosomic condition found only in females characterized by a (45,X)
karyotype.

Explanation

Turner syndrome is a monosomic condition found only in females characterized by a (45,X)
karyotype.

2. Which of the following is due to chromosomal breakage caused by sunlight or UV radiation?

Angelman syndrome

Fragile X syndrome

Miller-Dieker syndrome

Prader-Willi syndrome

Xeroderma pigmentosum

Xeroderma pigmentosum is an autosomal recessive genetic disorder in which affected individuals are hypersensitive to sunlight.

Explanation

Xeroderma pigmentosum is an autosomal recessive genetic disorder in which affected individuals are hypersensitive to sunlight.

3. Multifactorial inherited diseases involve which of the following?

Only a genetic component

Only an environmental component

Both a genetic and environmental component

Only one dominant gene

Only one X-linked gene

A multifactorial disease involves many genes that have a small, equal, and additive effect
as well as an environmental component.

Explanation

A multifactorial disease involves many genes that have a small, equal, and additive effect
as well as an environmental component.

4. Which of the following aneuploidy situations describes the Klinefelter syndrome?

Trisomy 13

Trisomy 18

Trisomy 21

(47,XXY)

(45,X)

Klinefelter syndrome is a trisomic condition found only in males characterized by a
(47,XXY) karyotype.

Explanation

Klinefelter syndrome is a trisomic condition found only in males characterized by a
(47,XXY) karyotype.

5. STRUCTURAL CHROMOSOMAL ABNORMALITIES Cri du chat syndrome is characterized by which of the following?

Catlike cry

Greek warrior helmet

Absence of the thymus gland

Chromosome 15q11-13 maternal imprinting

Chromosome 15q11-13 paternal imprinting

The cri du chat syndrome is also called cat's cry syndrome because affected children demonstrate a catlike cry.

Explanation

The cri du chat syndrome is also called cat's cry syndrome because affected children demonstrate a catlike cry.

6. DiGeorge syndrome is characterized by which of the following?

Catlike cry

Greek warrior helmet

Absence of the thymus gland

Chromosome 15q11-13 maternal imprinting

Chromosome 15q11-13 paternal imprinting

DiGeorge syndrome is characterized by immunodeficiency due to the absence of the thymus gland and by hypocalcemia due to the absence of the parathyroid glands.

Explanation

DiGeorge syndrome is characterized by immunodeficiency due to the absence of the thymus gland and by hypocalcemia due to the absence of the parathyroid glands.

7. Duchenne muscular dystrophy demonstrates which of the following inheritance patterns?

Mitochondrial inheritance

X-linked recessive

Autosomal dominant

Autosomal recessive

Duchenne muscular dystrophy demonstrates an X-linked recessive inheritance pattern

Explanation

Duchenne muscular dystrophy demonstrates an X-linked recessive inheritance pattern

8. Huntington disease demonstrates which of the following inheritance patterns?

Mitochondrial inheritance

X-linked recessive

Autosomal dominant

Autosomal recessive

Huntington disease demonstrates an autosomal dominant inheritance pattern.

Explanation

Huntington disease demonstrates an autosomal dominant inheritance pattern.

9. Aneuploidy occurs as a result of which of the following?

Dispermy

Failure of meiosis in a germ cell

Failure of the first cleavage division

Nondisjunction during meiosis

Trispermy

Aneuploidy occurs as result of nondisjunction during meiosis

Explanation

Aneuploidy occurs as result of nondisjunction during meiosis

10. Which of the following genetic diseases involves a mutation in a Cl- channel?

Huntington disease

Cystic fibrosis

Duchenne muscular dystrophy

Leber hereditary optic neuropathy

B. Cystic fibrosis is an autosomal recessive disease that involves a mutation in the CF gene that
encodes for a Cl- channel.

Explanation

B. Cystic fibrosis is an autosomal recessive disease that involves a mutation in the CF gene that
encodes for a Cl- channel.

11. Chronic myeloid leukemia is caused by a reciprocal translocation between band q34 on chromosome 9 and band q11 on chromosome 22. This is referred to as the

Chicago chromosome

Boston chromosome

St. Louis chromosome

Philadelphia chromosome

Baltimore chromosome

The reciprocal translocation t(9;22)(q34;q11) is referred to as the Philadelphia chromosome
and results in a fusion gene called the abl/bcr oncogene.

Explanation

The reciprocal translocation t(9;22)(q34;q11) is referred to as the Philadelphia chromosome
and results in a fusion gene called the abl/bcr oncogene.

12. Which of the following aneuploidy situations describes the Patau syndrome?

Trisomy 13

Trisomy 18

Trisomy 21

(47,XXY)

(45,X)

Patau syndrome is a trisomic condition characterized by the presence of an additional chromosome
13.

Explanation

Patau syndrome is a trisomic condition characterized by the presence of an additional chromosome
13.

13. NUMERICAL CHROMOSOMAL ANOMALIES Triploidy is a condition in which cells contain

46 chromosomes

69 chromosomes

23 chromosomes

45 chromosomes

47 chromosomes

Triploidy is a condition in which cells contain 69 chromosomes.

Explanation

Triploidy is a condition in which cells contain 69 chromosomes.

14. Which of the following is inherited entirely through maternal transmission?

Huntington disease

Cystic fibrosis

Duchenne muscular dystrophy

Leber hereditary optic neuropathy

Leber hereditary optic neuropathy involves a mutation in the ND4 gene located on mitochondrial
DNA. All mitochondrial DNA is inherited only from the mother because sperm (male)
mitochondria do not pass into the ovum at fertilization.

Explanation

Leber hereditary optic neuropathy involves a mutation in the ND4 gene located on mitochondrial
DNA. All mitochondrial DNA is inherited only from the mother because sperm (male)
mitochondria do not pass into the ovum at fertilization.

15. SINGLE-GENE INHERITED DISEASES Leber hereditary optic neuropathy demonstrates which of the following inheritance patterns?

Mitochondrial inheritance

X-linked recessive

Autosomal dominant

Autosomal recessive

Leber hereditary optic neuropathy demonstrates a mitochondrial inheritance pattern.

Explanation

Leber hereditary optic neuropathy demonstrates a mitochondrial inheritance pattern.

16. Prader-Willi syndrome is characterized by which of the following?

Catlike cry

Greek warrior helmet

Absence of the thymus gland

Chromosome 15q11-13 maternal imprinting

Chromosome 15q11-13 paternal imprinting

Prader-Willi syndrome involves a microdeletion in chromosome 15q11-13 derived from the
father.

Explanation

Prader-Willi syndrome involves a microdeletion in chromosome 15q11-13 derived from the
father.

17. Isochromosome Xq is sometimes found in individuals with which of the following syndromes?

Acute promyelocytic leukemia

Chronic myeloid leukemia

Turner syndrome

Klinefelter syndrome

Down syndrome

Isochromosome Xq is found in 20% of females with Turner syndrome.

Explanation

Isochromosome Xq is found in 20% of females with Turner syndrome.

18. Type I diabetes is a multifactorial disease that involves which of the following?

HLA Class I genes

HLA Class 11 genes

HLA Class II genes

HLA Class IV genes

Type I diabetes involve HLA Class II genes. The specific locus is called HLA-DR3 and HLADR4.

Explanation

Type I diabetes involve HLA Class II genes. The specific locus is called HLA-DR3 and HLADR4.

19. Which of the following is the most common translocation found in humans?

T(14q21q)

T(13q14q)

T(15;17)(q21;q21)

T(9;22)(q34;q11)

This robertsonian translocation is the most common translocation in humans. Carriers of
this translocation are clinically normal.

Explanation

This robertsonian translocation is the most common translocation in humans. Carriers of
this translocation are clinically normal.