App. B Genetic testing

Question 1

What are the three observed types of hereditary diseases

Answer 1

• A single gene mutation causes the hereditary disease
• A mutation in any one of multiple genes causes the
  hereditary disease
• The combination of genes plus the influence of outside
  factors causes the onset of the hereditary disease

Question 2

What are the three classifications of hereditary disease? Know the key points of each

Answer 2

• Mendelian Conditions
• Chromosomal Conditions
• Multifactorial Conditions

Question 3

Molecular analysis tests ____ or ________ and is useful when there is suspicion of a specific ____________ condition

Answer 3

DNA/ RNA/ Mendelian

Question 4

6 types of genetic testing

Answer 4

• Presymtomatic genetic testing
• Carrier genetic testing
• Newborn genetic screening
• Prenatal genetic testing
• Preimplantation genetic screening
• Direct-to-consumer genetic testing

Question 5

How many repeats does a normal HD gene contain? What are the triplet that is repeated

Answer 5

• contains up to 34 CAG repeats that are consecutive
• Repeats encode a string of glutamine amino acids in the huntingtin protein
• of more than 34 CAG repeats then it will become unstable

Question 6

What type of testing determines if a person is a heterozygous carrier for a recessive disease? If one partner is determined to not be a genetic carrier does the other partner need to be tested?

Answer 6

Carrier genetic testing
* The other partner does NOT need to be tested.

Question 7

Is the newborn genetic screening mandated in all 50 US States?

Answer 7

YES

Question 8

What is the main disease screened for using the Guthrie test?

Answer 8

Phenylketonuria (PKU)

Question 9

What is the Guthrie test also known by

Answer 9

as known as heel stick or PKU

Question 10

Prenatal genetic testing can look for which 3 abnormalities?

Answer 10

Inherited diseases, chromosomal abnormalities, and skeletal or developmental abnormalities

Question 11

Fetal cell sorting is done by and can identify which diseases?

Answer 11

• Cystic fibrosis
• Spinal muscular atrophy

Question 12

What is genetic counseling?

Answer 12

• integral part of medical genetics and is provided by specially trained genetic counselors
• aim to provide comprehensive, understandable medical information about a current condition or recurrence risk of a condition

Question 13

What analysis does the probability estimation methodology use?

Answer 13

Bayesian analysis determines the probability of a
certain genotype occurring in a certain family member
- Uses known or inferred genotype information and prior information from offspring produced by set of parents

Question 14

What is prior, conditional, and joint probability?

Answer 14

• prior probability of a genotype is determined; this is the likelihood that the hypothesis that an individual has a certain genotype is true
• conditional probability is calculated using
  information such as traits of other offspring of the same parents as the individual of interest
• joint probability is calculated by multiplying the prior probability by the conditional probability

Question 15

Mendelian Conditions

Answer 15

• mutation of a single gene
• may be inherited from one or both parents carrying he mutation or may be the result of a new mutation
• Six patterns of inheritance
• Autosomal, Sex linked, Mitochondrial
• Dominant or Recessive

Question 16

Multifactorial conditions

Answer 16

• influenced by multiple genes along with environmental factors
  
  • Diabetes is an example
• Inherited genetic variation may play a role in making some
  individuals more likely to develop the condition than others
• This increased likelihood is referred to as an “inherited
  susceptibility,” which may vary between populations
• This variation is often due to differing mutant allele
  frequencies in different populations

Question 17

Presymtomatic genetic testing

Answer 17

determines whether or not a person carries a mutation that will cause future disease; few diseases can be tested this way

Question 18

Carrier genetic testing

Answer 18

is more common; it determines if a person is a heterozygous carrier for a recessive disease

Question 19

Newborn genetic screening

Answer 19

mandated in all 50 US states, tests newborns for three dozen or more treatable, rare genetic diseases

Question 20

Prenatal genetic testing

Answer 20

identifies inherited diseases, chromosome abnormalities, and skeletal or developmental abnormalities

Question 21

Preimplantation genetic screening

Answer 21

for specific and limited circumstances, tests for hereditary diseases in fertilized embryos produced by in vitro fertilization

Question 22

Direct-to-consumer genetic testing

Answer 22

offered by for-profit companies, either duplicates medically available genetic carrier testing or provides information about
inheritance of genetic markers associated with certain hereditary conditions