Lecture 5: Pedigree Analysis And Genetic Testing

Question 1

Adrematoglyphia

Answer 1

The absence of ridges on the skin on the pads of the fingers and toes. This is an autosomal dominant mutation.

Question 2

Pedigree chart

Answer 2

A document I used by genealogist to study human family history

Question 3

What are the special features of human biology that hindered genetic research?

Answer 3

1 - controlled mating is not possible
2- long generation time
3 -small family size

Question 4

What are the ethical outline principles of the Belmont report

Answer 4

1 - respect for persons : informed consent - the individual must be acknowledged and respected

2 - beneficence: researcher obligation to do not harm and minimize all the risks

3 - justice: treat all individuals fair

Question 5

Proband

Answer 5

The person who the pedigree started with

Question 6

Autosomal recessive trait

Answer 6

Normally appear with equal frequency in bth sexes and seem to skip generations.

• cystic fibrosis, sickle cell, and tay sachs disease.
• usually appear in men and women equally
• more likely to appear in progeny or parents who are related

Question 7

Autosomal dominant traits

Answer 7

Normally appear equal frequency in bath sexes and so not skip generations

• affected people have at least one affected parent
  Unaffected people do not transmit the trait

Question 8

X linked recessive traits

Answer 8

Appear more often in males than in females

• are not passed from father to son
• a recessive allele (color blind) is masked in a female with a 2 X chromosomes

Question 9

X linked dominant

Answer 9

genetic conditions associated with mutations in genes on the X chromosome. A single copy of the mutation is enough to cause the disease in both males (who have one X chromosome) and females (who have two X chromosomes).

Question 10

Y links traits

Answer 10

Occur only in males and are passed from father to all his sons

• male infertility, supper hairy ears, XYY syndrome

Question 11

Dizygotic twins

Answer 11

Non identical twins

Have same genetic similarities as a brother or sister from different pregnancies

Question 12

Monozygotic twins

Answer 12

Identical twins

Has the exact same gene sequence. If twins are adopted then the developmental factors could be different due to environment

Question 13

Concordant trait

Answer 13

Trait shared by both members of a twin pair

• cancer
• death from acute infection

Question 14

Concordance

Answer 14

The percentage of twin pairs that are the same (concordant) for a trait

• means the presence if the same trait in both members of a pair of twins. The trait may not be the same
• asthma in identical twins = 67% and on fraternal = 37%

Question 15

What is Chloe’s law

Answer 15

In Missouri it requires all hospitals in MO to administer a pulse ox on every newborn