Genetics and Genetic Counselling

Question 1

Study of the way such disorder occur

Answer 1

Genetics

Question 2

Study of chromosomes by light microscopy and the method by which chromosomal aberrations are identified

Answer 2

Cytogenetics

Question 3

Basic units of heredity that determine both the physical and cognitive characteristics of people

Answer 3

Genes

Question 4

Composed of segments of DNA (Deoxyribonucleic acid) that are woven into strands in the nucleus of all body cells

Answer 4

Chromosomes

Question 5

Refers to his or her outward appearance or the expressions of genes

Answer 5

Phenotype

Question 6

Refers to his or her actual gene composition

Answer 6

Genotype

Question 7

The complete set of genes

Answer 7

Genome

Question 8

What is the numerical value of a complete set of genes?

Answer 8

50,000 - 100,000

Question 9

A person who has two like genes for a trait – two healthy genes, for example (one from the mother and one from the father)

Answer 9

Homozygous

Question 10

The genes differ (a healthy gene from the mother and an unhealthy gene from the father, and vice versa)

Answer 10

Heterozygous

Question 11

Either a person has two unhealthy genes (is homozygous dominant) or is heterozygous – with the gene causing the disease stronger than the corresponding healthy recessive gene for the same trait

Answer 11

Autosomal Dominant Disorders

Question 12

Tend to be biochemical or enzymatic

Answer 12

Autosomal Recessive Inheritance

Question 13

The disease does not occur unless two genes for the disease are present (homozygous recessive pattern)

Answer 13

Autosomal Recessive Inheritance

Question 14

Some genes for disorders are located on, and therefore transmitted only by, the female sex chromosome (the X-chromosome)

Answer 14

X-Linked Dominant Inheritance

Question 15

If the affected gene is dominant, only one X-chromosome with the trait need to be present for symptoms of the disorder to be manifested

Answer 15

X-Linked Dominant Inheritance

Question 16

The majority of X-linked inherited disorders are not dominant but recessive

Answer 16

X-Linked Recessive Inheritance

Question 17

When the inheritance of a recessive gene comes from both parents (homozygous recessive), it appears to be incompatible with life

Answer 17

X-Linked Recessive Inheritance

Question 18

A progressive neurologic disorder, characterized by loss of motor control and intellectual deterioration that is heterozygous inherited autosomal dominant disorder

Answer 18

Huntington disease

Question 19

Disorder results in muscle weakness

Answer 19

Facioscapulohumeral Muscular Dystrophy

Question 20

Disorder in which bones are exceedingly brittle

Answer 20

Osteogenesis Imperfecta

Question 21

Disorder of connective tissue that results in an individual being thinner and taller that usual and perhaps with associated heard disorder

Answer 21

Marfan Syndrome

Question 22

Accounts for 5% - 10% of breast cancer in women

Answer 22

Breast and Breast/Ovarian Cancer Syndrome

Question 23

Extra chromosome 13 and is severely cognitively challenged

Answer 23

Trisomy 13 - Patau Syndrome

Question 24

Has 3 copies of chromosome 18

Answer 24

Trisomy 18 - Edwards Syndrome

Question 25

The result of a missing portion of chromosome 5

Abnormal cry which sounds like a cat

Answer 25

Cri-Du-Chat Syndrome

Question 26

Has only one functional X-chromosome

Answer 26

Turner Syndrome

Question 27

Has two X-chromosomes and a Y-chromosome

Answer 27

Klinefelter Syndrome

Question 28

The most common cause cause of cognitive challenge in biologic males

Answer 28

Fragile X-Syndrome