Last Review & Stuff

Question 1

__________ is a single phenotype caused by mutations in genes at the same chromosomal locus.

Answer 1

Allelic Heterogeneticy

Question 2

__________ is a single phenotype caused by mutations in genes at different chromosomal loci.

Answer 2

Locus heterogeneity

Question 3

___________ is multiple phenotypes resulting from mutations in the same gene.

Answer 3

Clinical Heterogenetiy

Question 4

T/F-Balanced translocation carriers are not at risk to have unbalanced offspring.

Answer 4

False

Question 5

Contiguous gene syndrome:______.

Answer 5

Prader Willi Syndrome

Question 6

______ can result in mutation of a single gene. (PWS or AS)

Answer 6

AS

Question 7

PWS and AS are the best examples in humans of _______.

Answer 7

Imprinting

Question 8

Whole Genome sequencing mainly identifies mutations in ______.

Answer 8

Coding Exons

Question 9

________ is a single phenotype caused by any one of a multiple number of alleles or non-allele (locus) mutations.

Answer 9

Genetic Heterogenatiy

Question 10

Remember if a disorder is associated with thousands of repeats, it does not occur in the ________.

Answer 10

coding region

Question 11

If a woman is a carrier of a balanced Robertsonian translocation between chromosomes 14 & 21, how many chromosomes will she have?

Answer 11

45

Question 12

A woman and her brother are carriers of a balanced Robertsonian translocation between chromosomes 14 and 21. Who has the highest risk to have a child with Down Syndrome?

Answer 12

The risk is always higher in the FEMALE

Question 13

A woman has a balanced Robertsonian translocation between chromosomes 14 and 21. Her child has DS, how many chromosomes does the child have? How many #21’s?

Answer 13

46, 3 #21’s

Question 14

What is unique about turner syndrome?

Answer 14

only viable monosomy in humans!

Question 15

How many barr bodies do you see in a turner syndrome pt?

Answer 15

0

Question 16

What disorder does non disjunction always occur in male meiosis II?

Answer 16

47, XXY-Kleinfelters

Question 17

What is the underlying molecular mechanism for type I OI with DI?

Answer 17

Dominant Negative

Question 18

You need to figure out where to send a patient sample for genetic testing. What resource can you use to find an appropriate lab?

Answer 18

Genetic Testing Registry

Question 19

A couple has a son with a normally female disorder. Their subsequent risk is _____ than if a daughter had been affected, and the subsequent risk is _____ for a daughter than a son.

Answer 19

Higher…higher

Question 20

_______: Multiple genes contribute to phenotype, usually each with a small contribution; important in complex traits like diabetes.

Answer 20

Polygenic

Question 21

______: Genes AND environment contribute to phenotype

Answer 21

multifactoral

Question 22

What 3 factors increase recurrence risk for a multifactoral trait like clefting?

Answer 22

1. # of affected individuals (more=higher risk) 2.Severity (more severe=higher risk) 3.Sex (female is higher risk to pass it to a son)

Question 23

How is genetic testing different from other types of medical tests?

Answer 23

Implications for other FAMILY members!

Question 24

A 20 year old woman has PWS due to a parental deletion. If she gets pregnant, what is her risk to have a child with a significant genetic disorder?

Answer 24

50%