Medical Genetics - V. M. Zaporozhan 2005

Methods of Diagnosing Hereditary Diseases
Review Questions for Chapter 10

1. What is portrait Diagnostics? The Use of computer diagnostic software and Databases.

2. Indications for Cytogenetic diagnostics. Karyotyping. Methods of routine and differential chromosome staining.

3. Molecular Cytogenetic methods.

4. Determination of Sex Chromatin.

5. Indications for DNA diagnostics. Molecular Genetic Methods.

6. Stages of DNA diagnostics using the Polymerase Chain Reaction (PCR). Modifications of PCR.

7. Use of Restriction Endonucleases, restriction fragment length polymorphism (RFLP) analysis, Southern blot Hybridization, and DNA Sequencing.

8. Direct and Indirect methods of DNA diagnostics.

9. Application of Molecular genetic methods in forensic medicine.

10. Dermatoglyphics method. Dermatoglyphic features in Chromosomal Disorders.

11. Biochemical Methods. Indications for biochemical diagnostics.

Test and Study Questions

Choose a single answer.

1. An indication for cytogenetic analysis is:

A. Hepatosplenomegaly, cataract, intellectual disability

B. Recurrent Pregnancy loss and a history of stillbirths

C. Intolerance to certain foods, hemolytic crises

D. Progressive loss of acquired skills, seizures, spastic paralysis

E. Neurological manifestations (seizures, decreased or increased Muscle tone, spastic paresis)

2. Oligophrenia in a child combined with malformations and minor developmental anomalies is an indication for:

A. Karyotyping

B. Molecular cytogenetic diagnostics

C. Biochemical diagnostics

D. Dermatoglyphic examination

E. Molecular genetic testing

3. All of the following methods are used for the Diagnosis of chromosomal disorders, except:

A. Karyotyping

B. Determination of sex chromatin

C. Biochemical

D. DNA diagnostic methods

E. Dermatoglyphic

4. The method of precise diagnosis for chromosomal disorders is:

A. Cytogenetic

B. Dermatoglyphic

C. DNA diagnostics

D. Clinical and Genealogical

E. Specific biochemical diagnostics

5. A family consulted a medical genetics clinic regarding recurrent pregnancy loss. The woman's history shows four spontaneous abortions in the first trimester of pregnancy. This situation is an indication for:

A. Clinical and genealogical family evaluation and karyotyping (karyotyping of both husband and wife)

B. Clinical and genealogical family evaluation and selective biochemical screening

C. Clinical and genealogical family evaluation and molecular cytogenetic diagnostics

D. Clinical and genealogical family evaluation and molecular Genetic Testing of the spouses

E. Clinical and genealogical family evaluation and The Use of the Dermatoglyphic method

6. Karyotyping is one of the genetic methods. Phytohemagglutinin is used in the preparation of metaphase plates. What is its effect on lymphocytes?

A. Stimulates Cells to undergo mitosis

B. Destroys the mitotic spindle

C. Arrests mitosis at metaphase

D. Arrests mitosis at anaphase

E. Causes Swelling of Chromosomes and cells

7. Karyotyping is one of the genetic methods. Colchicine is used in the preparation of metaphase plates. How does it affect lymphocytes?

A. Stimulates cells to undergo mitosis

B. Causes Cell swelling

C. Arrests mitosis in metaphase

D. Arrests mitosis in anaphase

E. Causes chromosome swelling

8. The FISH method is one of the most sensitive cytogenetic techniques. However, it is expensive and is used when other cytogenetic methods prove ineffective. Which clinical situation can be an indication for using this method?

A. A newborn with Clinical symptoms of Down syndrome

B. A 13-year-old girl with clinical symptoms of Turner syndrome

C. A man with oligozoospermia, eunuchoid habitus, and gynecomastia

D. An 8-month-old infant with psychomotor retardation, hypopigmentation, and a specific urine odor

E. A 6-year-old girl with developmental delay and clinical symptoms of Angelman syndrome

9. Detection of sex chromatin clumps (Barr bodies) in oral mucosa epithelial cells is a rapid diagnostic method for:

A. Down syndrome

B. Turner syndrome

C. Patau syndrome

D. Y polysomy

E. Duchenne muscular dystrophy

10. A boy with Klinefelter syndrome has a 49,XXXXY karyotype. How many Barr bodies can be found in his buccal epithelial cells?

A. 0

B. 1

C. 2

D. 3

E. 4

11. A woman with oligophrenia has a 48,XXXX karyotype. How many sex chromatin clumps can be found in a buccal smear?

A. 0

B. 1

C. 2

D. 3

E. 4

12. A man with oligophrenia and symptoms of hypogonadism has a 48,XYYY karyotype. How many Barr bodies can be found in a buccal mucosa scrape?

A. 0

B. 1

C. 2

D. 3

E. 4

13. Which of the following methods are used to diagnose Klinefelter syndrome?

A. Karyotyping, DNA diagnostics, Syndromological Analysis

B. Syndromological analysis, biochemical methods, DNA diagnostics

C. Genealogical method, syndromological analysis

D. Syndromological analysis, karyotyping, sex chromatin determination

E. Syndromological analysis, biochemical method, karyotyping

14. The proband is a 9-month-old boy. The mother complains of developmental delay starting from 4 months of age, lethargy, drowsiness, and three episodes of seizures. The boy exhibits pronounced muscle hypotonia, fair Skin with eczematous rashes, light brown Hair, bright blue eyes, and a "mousy" odor of sweat and urine. For further evaluation, the first step should be:

A. Karyotyping

B. Clinical and genealogical family assessment

C. Selective biochemical screening

D. Sex chromatin determination

E. Molecular genetic testing

15. The polymerase chain reaction is used in all of the following cases, except:

A. Diagnosis of Monogenic Disorders

B. Genomic fingerprinting in forensic medicine

C. Diagnosis of Congenital Malformations

D. Diagnosis of oncological diseases

E. Diagnosis of infectious diseases

16. Sickle-Cell Anemia is caused by a single nucleotide substitution (A → T) that abolishes a restriction site for the Mst II restriction enzyme. This feature allows the diagnosis of sickle-cell anemia using:

A. Sequencing

B. Allele-specific oligonucleotide analysis

C. RFLP analysis

D. FISH assay

E. Southern blotting

17. A healthy young couple sought MEDICAL Genetic Counseling. Their first child, a boy, was born with cystic fibrosis. Molecular genetic testing of the parents revealed that both are carriers of the F508 mutation in the Gene encoding the cystic fibrosis transmembrane conductance regulator. During the second pregnancy, chorionic villus sampling was performed to obtain chorionic tissue. Further Analysis of the chorionic tissue requires:

A. Molecular genetic testing

B. Cytochemical studies

C. Karyotyping

D. Sex chromatin analysis

E. FISH assay