Probability in Genetics

Key Questions

• What is an example probability in genetics practice problem?

  Answer:

  Example: Suppose a mother and father is both heterozygous for the characteristics of brown eyes and brown hair, ie they have brown eyes and brown hair but carry the recessive gene for blond hair and blue eyes.
  Calculate the probability that they would produce a blue-eyed, blond-haired boy as a child.

  Explanation:

  Answer:
  Since 1 gene from each parent is given for a character trait, together with the sex determination being carried on the gonosome (23rd chromosome), there is a 1 in 4 chance of each characteristic (blue eyes and blond hair) and a 1 in 2 chance of a boy as opposed to a girl.
  Therefore the overall combined probability may be found by using the multiplication principle as follows :
  #1/4x1/4x1/2 = 1/32# ie a 0,03125 probability or a 3,125% chance of it happening.

  Trevor Ryan. · 1 · Sep 23 2015

• What is an example probability in genetics practice problem?
• What information does a punett square provide?
• When 2 heterozygotes were crossed with each other i.e. #AaBb# x #AaBb#, the progeny showed: (i) A_B_ = 400 (ii) A_bb = 310 (iii) aaB_ = 290 (iv) aabb = 200 Does this prove Mendelian ratio? Find with a chi square test. (A and B- dominant)
• Given the following information, what is the probability that they will have a daughter with hemophilia?
• What is the probability that the son will be a carrier of the recessive allele?
• How do you do probabilities with punnett squares?
• What is the probability of having two autistic kids?
• What is the probability that all four are normal? That three will be normal and one albino? Two normal and two albino? One normal and three albino? All four albino?
• What is the probability that the first son of a woman whose brother is affected will be affected? What is the probability that the second son of a woman whose brother is affected will be affected if her first son was affected?
• What phenotypes would this cross produce and in what ratios?
• What can the principles of probability can be used for?
• What is the probability that their first son will have hemophilia?
• A woman whose brother had cystic fibrosis marries a man who had a child with cystic fibrosis from a previous marriage. They plan to have 3 children. What is the that only one of the 3 will have cystic fibrosis?
• If a person with type O blood has a baby with a person who has type AB blood, then what blood type will the baby have?
• The allele for curly hair is incompletely dominant. If a mother is homozygous for curly hair and the father is homozygous for straight hair, what percentage of the offspring will exhibit characteristics of both parents?
• An #F_1# plant that is homozygous for shortness is crossed with a heterozygous # F_1# plant. What is the probability that a seed from the cross will produce a tall plant?
• What is represented by a pair of lowercase letters, such as tt, in a Punnett square?
• Question #ba220
• Question #61451
• If the frequency of the #p# allele is .63 in the population then what is the frequency of the #q# allele?
• Why is crossing over so important to a species?
• Why are small populations more prone to genetic disease?
• Are calculated genotypic frequencies necessarily the same as observed genotypic frequencies?
• Question #741a4
• Question #16990
• Question #c4c81
• A woman who is a carrier of hemophilia is married with colour blind man. Than what will be the probability of sons to be colorblind..? A) 25% B) 50% C) 75% D) 100% E) None