Biology

Human Genetics and Disorders

882 Questions

Human Genetics and Disorders covers the inheritance patterns, genetic mutations, and molecular basis of hereditary diseases. Topics include sex-linked traits, cancer genetics, and metabolic disorders. This section tests knowledge critical for biology exams and general science papers.

Genetic mutationsInherited disordersCancer geneticsGenetic testingMendelian inheritance

Human Genetics and Disorders Questions

Multiple choice

On examination it was found that a boy was HLA-DR2 positive. He is at a risk of developing which of the following disease?

  1. Insulin-dependent (type I) diabetes

  2. Ankylosing spondylitis

  3. Multiple sclerosis

  4. Rheumatoid arthritis

  5. Myasthenia gravis
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

Individuals with HLA-DR2 are more at risk of developing multiple sclerosis than those with other HLA-DR specificities. Thus a higher frequency of HLA-DR2 is found in MS patients versus the normal population.

Multiple choice

Rh–factor incompatibility leads to

  1. anaemic condition in foetus

  2. leukaemia in foetus

  3. Both 1 and 2

  4. None of these
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Rh–factor incompatibility leads to anaemic condition in foetus.

Multiple choice

Which of the following is an autosomal dominant genetic disorder that causes unwanted blood vessel formation in skin, mucosa, lungs, liver and brain?

  1. Congenital generalised lipodystrophy

  2. Ehlers-Danlos syndrome

  3. Osler-Weber-Rendu disease

  4. Hemochromatosis

  5. Malignant melanoma
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

This option is correct. Osler-Weber-Rendu disease is an autosomal dominant genetic disorder that causes unwanted blood vessel formation in the skin, mucosa, lungs, liver and brain.

Multiple choice

Which of the following is an exceedingly rare autosomal recessive disorder which causes oculocutaneous albinism, bleeding problems due to a thrombocyte's oddity and deposit of an unusual fat-protein compound?

  1. Wilson's disease

  2. Menkes syndrome

  3. Occipital horn syndrome

  4. Hornstein-Knickenberg syndrome

  5. Hermansky-Pudlak syndrome
Reveal answer Fill a bubble to check yourself
E Correct answer
Explanation

This option is correct. Hermansky-Pudlak syndrome is an exceedingly rare autosomal recessive disorder which causes oculocutaneous albinism, bleeding problems due to a thrombocyte's oddity and deposit of an unusual fat-protein compound.

Multiple choice

Which of the following disorders is incorrectly described?

  1. Trichothiodystrophy - autosomal recessive inherited disorder that causes brittle hair

  2. Classical homocystinuria - inherited disorder of the metabolism of the methionine

  3. Familial melanoma syndrome - unusual nevi and multiple inherited melanomas

  4. Chédiak-Higashi syndrome - benign skin tumor derived from the hair matrix

  5. WHIM syndrome - congenital immunodeficiency disorder that causes chronic non-cyclic neutropenia
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

This option is correct. Chédiak-Higashi syndrome is an autosomal recessive disorder that arises due to mutation of a lysosomal trafficking regulator protein that causes decrease in phagocytosis.

Multiple choice

Which of the following is a congenital neurological and skin disorder that is caused by somatic activating mutation that occurs in the GNAQ gene?

  1. Progressive osseous heteroplasia

  2. Sturge-Weber syndrome

  3. Plate-like osteoma cutis

  4. Port-wine stain

  5. Capillary hemangioma
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

This option is correct. Sturge-Weber syndrome is a congenital neurological and skin disorder that is caused by somatic activating mutation that occurs in the GNAQ gene.

Multiple choice

Match the following ||| |---|---| |List - I | List - II| |P. Ehlers-Danlos syndrome|1. Autosomal dominant disorder| |Q. Acrokeratosis verruciformis|2. X-linked recessive connective tissue disorder| |R. Louis-Bar syndrome|3. X-linked congenital disorder| |S. Orofaciodigital syndrome 1|4. Autosomal recessive disorder|

  1. P - 2, Q - 1, R - 4, S - 3

  2. P - 4, Q - 1, R - 2, S - 3

  3. P - 2, Q - 3, R - 4, S - 1

  4. P - 3, Q - 2, R - 1, S - 4

  5. P - 4, Q - 2, R - 3, S - 1
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

This option is correct. Ehlers-Danlos syndrome is an X-linked recessive connective tissue disorder. Acrokeratosis verruciformis is an autosomal dominant disorder. Louis-Bar syndrome is an autosomal recessive disorder. Orofaciodigital syndrome 1 is an X-linked congenital disorder.

 

Multiple choice

Match the following:

 
Column - I Column - II
P. Zinsser-Cole-Engman syndrome 1. Rare recessive genetic disorder of skin with poor wound healing
Q. Urbach-Wiethe disease 2. Autosomal dominant disorder caused by mutations in a connexin gene, GJB6/connexin-30
R. Mendes da Costa syndrome 3. Rare progressive congenital disorder with a highly variable phenotype
S. Clouston syndrome 4. Rare genetic lysosomal storage disease, inherited in an X-linked manner
5. Rare autosomal dominant disorder caused by the mutations in genes encoding for connexin channels proteins in the epidermis

  1. P - 3, Q - 1, R - 5, S - 2

  2. P - 5, Q - 1, R - 4, S - 2

  3. P - 3, Q - 4, R - 5, S - 2

  4. P - 2, Q - 3, R - 4, S - 1

  5. P - 1, Q - 4, R - 5, S - 3
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Correct answer. Zinsser-Cole-Engman syndrome is a rare progressive congenital disorder with a highly variable phenotype. Urbach-Wiethe disease is a rare recessive genetic disorder of skin with poor wound healing. Mendes da Costa syndrome is a rare autosomal dominant disorder caused by the mutations in genes encoding for connexin channels proteins in the epidermis. Clouston syndrome is an autosomal dominant disorder caused by mutations in a connexin gene, GJB6/connexin-30.  

Multiple choice

Which of the following is a genetic disorder that causes varying degrees of deafness, minor defects in structures and pigmentation inconsistencies?

  1. Witkop syndrome

  2. Griscelli syndrome

  3. Waardenburg syndrome

  4. Neurofibromatosis type I

  5. Ichthyosis hystrix
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

This option is correct. Waardenburg syndrome is a genetic disorder that causes varying degrees of deafness, minor defects in structures and pigmentation inconsistencies.