FTM 63 - OMICS: The Impact of the Human Genome Project on Medical Genetics

Question 1

What is the major ethical issue surrounding advances in the field of medical genetics?

Answer 1

Who should have access to this information?

Question 2

What is the annotation process of the human genome project? What is wrong with this process?

Answer 2

The annotation process aimed to identify the functional parts of the genome by finding ORFs using start, stop, splicing, tailing, and other regulatory sequences.

The process will sometimes miss genes not translated into protein, very small ORFs, small genes within larger genes, and genes on opposing strands.

Question 3

Do larger chromosomes always have more genes than smaller ones?

Answer 3

Normally but not always

Question 4

Why are chromosomes 13, 18, and 21 the only autosomes that can be found as trisomy and compatible with life?

Answer 4

They have the fewest genes on them

Question 5

What are SSRs, VNTRs, and LCRs?

Answer 5

Simple Sequence Repeats - di, tri, or tetra nucleo tide repeats

Variable Number Tandem Repeats - slightly longer SSRs

Low Copy Repeats - very long repeats; up to thousands of base pairs

Question 6

Which transposon encodes a reverside transcriptase and which one contains the Alu sequence?

Answer 6

LINES encode RTs

SINES contain the Alu sequence

Question 7

What are the three general types of pseudogenes?

Answer 7

Question 8

What are the examples of vistigial and non-expressed duplicated pseudogenes we need to know?

Answer 8

Vestigial - the gene for Vitamin C

Non-express duplicated - one of the globin genes

Question 9

How is a processed pseudogene formed?

Answer 9

Question 10

What is the most repetitive DNA in the genome?

Answer 10

Transposons

Question 11

What are the two ways that transposons can lead to disease?

Answer 11

Question 12

How are repetitive sequences utilized in forensic medicine?

Answer 12

PCR is done to amplify highly polymorphic single locus regions like SSRs or VNTRs and the products are ran on a gel to establish a DNA fingerprint

Question 13

What is multiplex PCR?

Answer 13

PCR where more than one DNA sequence is amplified at a time

Question 14

What is thought to be the engine of evolution? Why?

Answer 14

Question 15

How can gene duplications lead to genetic disease? Provide two examples

Answer 15

It can lead to inapropriate crossing over during meiosis which may lead to loss of a gene.

The red and green pigment genes are very similar and the green pigment gene is normally duplicated several times. This could cause and red-green pigment crossover during meiosis resulting in a X-chromosome missing a green pigment gene and Red-Green color blindness

Chromosome 16 contains multiple α-globin genes which could result in them being deleted during crossover in meiosis causing α-thalessemia

Question 16

What are the three main types of microarray and what are they usually used for?

Answer 16

Question 17

What is a haplotype? Whate does that have to do with SNP CHIP?

Answer 17

A haplotype is a set of DNA variations, or polymorphisms, that tend to be inherited together. Many SNPs inherit together with certain disease allels. By using a SNP CHIP you can determine a persons haplotype without individual genome sequencing

Question 18

What does a genome wide association study do and what does it aim to learn? What are some problems with GWASs?

Answer 18

It uses SNP CHIP to scan 1000’s of SNPs among 1000’s of people in search for genetic variations associated with a particular disease. This is done in an attempt to uncover genetic determinants of multifactorial disease.

GWASs will not find rare variants that could be responsible for a disease. Also, correlation does not mean causation; results may be misleading.

Question 19

What is a transcriptome?

Answer 19

The sum total of all of the mRNA in a particular cell under a particular condition

Question 20

Define these “omics” - epigenomics, transcriptomics, variomics, proteomics

Answer 20

Question 21

What is the human epigenome project trying to do?

Answer 21

Question 22

Methylation of CpG islands are associated with __________ gene expression of nearby genes.

Answer 22

Reduced