Irwins q's

Question 1

Gene

Answer 1

Segment of DNA that encodes a protein, BRCA1 gene

Question 2

Allele

Answer 2

Different versions of the same gene, Blood type A B

Question 3

Homozygous

Answer 3

Having 2 identical allels, AA aa

Question 4

Heterozygous

Answer 4

Two different alleles, Aa

Question 5

Dominant

Answer 5

An allele that reduces the ability of recessive allele, huntingtons

Question 6

Recessive

Answer 6

AN allele that is reduced by the dominant, cystic fibrosis

Question 7

Codon

Answer 7

Sequence of AA that specifies a protein, AUG PS

Question 8

Polymorphism

Answer 8

Common genetic vriation, MTHFR

Question 9

Haploid

Answer 9

Cells containing only 1 set of chromosomes, 23 egg cells

Question 10

Hiploid

Answer 10

2 sets, somatic cells 46

Question 11

Genome

Answer 11

DNA containing all its genetic components

Question 12

Exon

Answer 12

Coding region of a gene expressed as a protein

Question 13

Intron

Answer 13

Non-coding region that’s removed during mRNA processing

Question 14

Autosomal dominant inheritance

Answer 14

Single copy of gene causes mutation,

Feature: 50% chance. passes generations, HTT causes huntingtons

Question 15

Autosomal recessive inheritance

Answer 15

Two copies of mutated gene required to cause the inheritance

Features: Gene from each parent inherited, Parent may be asymptomatic, e.g cystic fibrosis from CTFHR

Question 16

X- linked inheritance

Answer 16

Mutation in X - Chrom

Females are carriers but need 2

e.g DMD, duchene muscular dystrophy

Question 17

X-linked dominant

Answer 17

Single mutation on the x allele

Fragile X syndrome FMR1 mutation

Question 18

Genetic testing

Answer 18

Confirms a carrier

determines chance of person inheriting or developing

Question 19

Pre implantation genetic diagnosis

Answer 19

Person with disorder can have kids without having it

egg fertilised 3-5 days embryo divides

Cell removed and DNA analysed, determines which don’t have mutation

Then transferred to uterus

Question 20

Pre natal testing

Answer 20

Performed when risk of chromosomal abnormality

2 types invasive and non invasive

Question 21

Amniocentesis

Answer 21

15-17 weeks

Samples amniotic fluid, 1-500 C

Question 22

Chronic villus sampling

Answer 22

10-11 weeks. placental tissue sample

sim MC

Question 23

Cordocentesis

Answer 23

16 weeks

Foetal blood sample in umbilical cord

determines chromosomal abnormalities

higher risk

Question 24

Maternal serum screening

Answer 24

Blood test for DS, Low AFP _ high HCG = DC

Question 25

New born screening

Answer 25

Carried out after birth

Detects for high levels of phenylalalnine

Question 26

Heal prick test

Answer 26

Blood from heal on absorbent card

air dryed and check for ph levels

Question 27

Predictive testing

Answer 27

Identifies mutations that inc the risk of patient developing disorder

mutation = development of disorder possible

Question 28

Presymptomatic testing

Answer 28

Determines if a person will develop disorder before signs appear

used to check for huntingtons