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1

What is complex inheritance?

Inheritance that does not follow mendelian inheritance

2

What are some inheritance patterns of complex inheritance?

Incomplete penetrance

Genomic imprinting

Extranuclear inheritance

Anticipation

3

What is incomplete penetrance?

People have a mutation but do not develop the symptoms of the disorder

4

What is genomic imprinting?

Genes expressed only from one chromosome, parent of origin dependent

(maternal or paternal gene is switched of)

5

What is extranuclear inheritance?

Transmission of genes that occur outside the nucleus, such as the mitochondria

6

What is anticipation?

Symptoms of a genetic disorder become apparent at an early age

7

8

What is penetrance?

The frequency with which a trait is manifested by individuals carrying the gene

9

What gene is usually responsible for cystic fibrosis?

CFTR

10

What are genetic modifiers?

Genes that have small quantative effects on the level of expression of another gene

11

What is polymorphism?

Genetic variants of a gene

12

What is also important for the onset of genetic diseases?

Environmental factors

13

What are epigenetic modifications?

Heritable changes in gene function that cannot be explained by changes in DNA sequences

14

What is uniparental disomy?

2 copies of a chromosome come from the same parent instead of 1 from each

15

What are the 2 kinds of uniparental diploidy?

Gynotypic (2 maternal genomes)

Androgenic (2 paternal genomes)

16

17

What is gynogenic uniparental diploidy?

2 maternal genomes:

 

Mass of embryo

Ovarian teratoma

18

What is andogenic uniparental diploidy?

2 paternal genomes:

 

Mass of placenta

Hydatidiform mole

19

What are examples of imprinting disorders?

Angelman syndrome

Prader-Willi syndrome

20

Where is mitochondiral inheritance from?

Maternal

21

Which has more mutations out of the nuclear genome and the mitochondria?

Mitochondria due to:

 

Lack of DNA repair systems

Lack of protective proteins such as histones

Damaged by reactive oxygen species

22

What is polyploidy?

Cell having more than 2 pairs of chromosomes

23

What is homoplasmy?

Cell whose mitochondrial DNA is all identical

24

What is heteroplasmy?

Cells whose mitochondrial DNA is not all identical

25

What are the 3 major myopathies?

Myoclonic epolepsy

Mitochondrial myopathy

Chronic progressive external ophthalmoplegia

26

What does mitochondrial disease affect?

Tissues with high metabolic demand

27

How can a baby have 3 genetic parents?

Sperm from dad

Egg from a mum

Mitochondrial DNA from another mum

28

What are examples of anticipation diseases?

Triple repeat diseases:

 

Huntington's disease

Myotonic dystrophy

Fragile X syndrome