Medical Genetics MCQs
1. What is the fundamental unit of heredity that carries genetic information from one generation to the next?
A) Chromosome
B) Gene
C) DNA
D) RNA
Answer: B) Gene
2. Which term describes the observable characteristics or traits of an individual?
A) Genotype
B) Phenotype
C) Allele
D) Karyotype
Answer: B) Phenotype
3. What type of genetic inheritance pattern requires only one copy of a mutated gene to express the trait or disorder?
A) Autosomal recessive
B) Autosomal dominant
C) X-linked recessive
D) Mitochondrial
Answer: B) Autosomal dominant
4. Which genetic disorder is caused by a mutation in the CFTR gene and primarily affects the respiratory and digestive systems?
A) Cystic fibrosis
B) Sickle cell anemia
C) Huntington’s disease
D) Hemophilia
Answer: A) Cystic fibrosis
5. What is the expected probability of an offspring inheriting a recessive genetic disorder if both parents are carriers?
A) 25%
B) 50%
C) 75%
D) 100%
Answer: A) 25%
6. Which type of genetic mutation involves the addition of one or more nucleotides in the DNA sequence?
A) Deletion
B) Insertion
C) Substitution
D) Duplication
Answer: B) Insertion
7. What is the primary purpose of genetic counseling?
A) To provide information about genetic disorders and risks
B) To perform surgical procedures
C) To administer medications
D) To conduct psychological assessments
Answer: A) To provide information about genetic disorders and risks
8. What genetic condition is characterized by the presence of an extra chromosome 21?
A) Turner syndrome
B) Down syndrome
C) Klinefelter syndrome
D) Edwards syndrome
Answer: B) Down syndrome
9. Which type of inheritance pattern involves a gene located on the X chromosome and manifests in females only if both X chromosomes carry the mutation?
A) X-linked dominant
B) X-linked recessive
C) Autosomal dominant
D) Autosomal recessive
Answer: B) X-linked recessive
10. The BRCA1 and BRCA2 genes are primarily associated with an increased risk for which type of cancer?
A) Lung cancer
B) Breast and ovarian cancer
C) Prostate cancer
D) Colon cancer
Answer: B) Breast and ovarian cancer