SNP 101

Question 1

What does SNP stand for?

Answer 1

Single Nucleotide Polymorphism

Question 2

What is a SNP?

Answer 2

a variation of one nucleotide at a single position in a DNA sequence that occurs in >1% of the population

Question 3

What is Myriad’s Variant Classification (Polymorphism) 5 catergories?

Answer 3

Polymorphism
Favorable Polymorphism
Variant of Uncertain Significance (VUS)
Suspected Deleterious
Deleterious

Question 4

Are all Polymorphisms benign

Answer 4

NO (FALSE)

Question 5

What is the most common genetic variation?

Answer 5

SNP

Question 6

SNP account for what % of genetic variations?

Answer 6

90%

Question 7

A SNP is a variation of one nucleotide at a single position in the DNA sequence that occurs in greater than __% of a certain population?

Answer 7

1%

Question 8

SNPs are generally associative of a disease, not causative. TRUE or FALSE?

Answer 8

TRUE

Question 9

A SNP association found in a specific population can be generalized to all populations. TRUE or FALSE

Answer 9

FALSE

Question 10

SNPs can be associated with an increased or decreased risk of developing a certain disease. TRUE or FALSE?

Answer 10

TRUE

Question 11

The Mavaddat study. 77 breast cancer associated SNPs were evaluated to construct a scoring system referred to as the?

Answer 11

Polygenic Risk Score (PRS)

Question 12

The findings from the Mavaddat study showed that the use of SNP analysis to generate a Polygenic Risk SCore could help stratify breast cancer risk only in patients with a family history of breast cancer. TRUE or FALSE

Answer 12

FALSE

Question 13

What is Myriad’s lifetime commitment?

Answer 13

Myriad has a lifetime commitment to variant classification and curation. Myriad is dedicated to providing patients and providers with clinically actionable results.

Question 14

What study looked at frequency of Variant reclassification and types of variants reclassified?

Answer 14

Mersch, JAMA 2018

Question 15

What study assessed the value of combining the effect of 77 individual SNPs for personalized risk stratification in women to guide preventive and screening strategies for Breast Cancer

Answer 15

Mavaddat, Journal of National Cancer Institute, 2015

Question 16

What are the 5 distinct classifications for genetic variants? Mersch JAMA 2015

Answer 16

Benign (Polymorphism)
Likely Benign (Favor Polymorphism)
Variant of Uncertain Significance (VUS)
Likely Pathogenic (Suspected Deleterious)
Pathogenic (Deleterious)

Question 17

In the Mersch study, What was the rate of reclassification from VUS to pathogenic/likely pathogenic? downgraded to Pathogenic/L pathogenic?

Answer 17

8. 7%

91. 2%

Question 18

What is the conclusion of the Mersch study?

Answer 18

The rate of Variant reclassification may be LAB-DEPENDENT