DNA to Genes to Chromosomes (Part 1) Flashcards Preview

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Flashcards in DNA to Genes to Chromosomes (Part 1) Deck (21):
1

Which strand can be used as a primer for PCR or as an ASO probe for detection of mutations?

Anti-parallel

2

What is an example of a epigenetic modifications that regulates the rate at which transcription occurs

Methylation

3

What are the types of DNA sequences that we have?

1) Nuclear
2) Extragenic
3) Mitochondrial

4

What are the types of extragenic DNA?

-Tandem repeat
-Interspersed

5

What are the categories of Nuclear DNA?

1) Nuclear genes
2) Multigene families

6

What are the sub-types of Nuclear Gene DNA?

Unique single copy

7

What are the types of Nuclear Multigene DNA?

1) Classic gene families
2) Gene superfamilies

8

What are characteristics of Nuclear Genes?

-25,000-30,000 unique copy genes in nuclear genome
-Heterochromatic and centromeric regions are generally non-coding
-Variable in size
-Unique copy genes code for enzymes, hormones, receptors, structural and regulatory proteins
-Exon sequences of genes are interspersed by introns

9

In regards to Nuclear genes, where is the highest gene density?

subtelomeric region

10

What are unique single copy genes under the category of Nuclear coding DNA?

Unique sequences in the genome that code for one protein: receptors, enzymes, hormones, structural elements of the cell, etc.

11

What are multigene families under the category of Nuclear Coding DNA?

Multigene families (can be clustered or dispersed): Genes with similar functions that have arisen by gene duplication

12

Multigene families, a type of Nuclear Coding DNA, can be further subdivided into what?

1) Classic gene families
2) Gene superfamilies

13

What are classic gene families?

multicopy genes that show a high degree of homology (e.g. HOX genes and genes for rRNAs, tRNAs)

14

What are gene superfamilies?

multicopy genes with similar function but limited gene homology (e.g. HLA genes, T-cell receptors)

15

What are the characteristics of extragenic DNA?

-constitute majority of the human genome
-predominantly transcriptionally inactive
-May play role in regulation of gene expression

16

Tandem repeat DNA sequences consist of what?

blocks of tandem repeats of non-coding DNA:
-variable number of tandem repeats (VNTR),
-short tandem repeats (STR)

17

Describe VNTR and STR.

polymorphic and inherited in a co- dominant fashion

18

What is used as the basis of DNA fingerprinting

STR variations

19

Tandem repeats: Are sequences repeated many times, that can be highly dispersed or restricted to one or a few locations. (T/F)

TRUE!!!

20

What are the subgroups of Tandem Repeat Extragenic DNA?

-Satellite
-Minisatellite
-Microsatellite

21

Satellite DNA are repeated sequences of DNA usually clustered around centromeres of chromosomes (T/F)

TRUE!!!