Lecture 4

Question 1

Cystic Fibrosis Mutation

Answer 1

Caused by mutations in CFTR gene (Cystic Fibrosis Transmembrane Conductance Regulator); generally recessive

Question 2

Probability

Answer 2

Likelihood of the occurrence of a particular event; used in genetics to predict the outcome of a genetic cross

Question 3

Conditional Probability

Answer 3

Probability of an event (A), given that another (B) has already occurred

Example: A cross is made between 2 heterozygous parent plants. What is the probability that a tall offspring plant is homozygous?

Tt x Tt = 1/4 TT + 1/2 Tt + 1/4 tt; but “tt” cannot take place, so there is a 1/3 chance of the plant being TT

Question 4

Binomial Expansion

Answer 4

Mathematical formula to determine the probability of an outcome; formula = (p+q)^n where

p = the frequency of one outcome
q = the frequency of the other outcome
n = number of events
p+q = 1

Formula expanded out with example is on Slide 30

Question 5

Dihybrid Crosses

Answer 5

Crosses involving 2 traits with differing alleles

Question 6

Law of Independent Assortment

Answer 6

Alleles encoding different traits on different chromosomes separate independently of one another; this results from the independent separation of chromosomes in anaphase 1 of meiosis

Question 7

Chi-Square Goodness of Fit

Answer 7

Statistical test that indicates the probability that the difference between the observed and expected values is due to chance; this assumes that the sample data is a random sample of a larger population, the sample size is sufficiently large to prevent small sample error, and the observations are independent of each other

Question 8

Degrees of Freedom

Answer 8

Number of values (characteristics such as different flower colors) that are free to vary minus 1

Question 9

Multiple Testing Correction

Answer 9

Refers to re-calculating probabilities obtained from a statistical test which was repeated multiple times