# Thread: Probability of that VHS is transmitted

1. ## Probability of that VHS is transmitted

What is the probability that reproduction will lead to the transmission of VHS from an infected male to an uninfected female that is heterozygous for the mutant allele?

Note: Use facts
#1:heterozygous (Gg) for mutation reduces the transmission rate of VHS by 10%
#4: transmission rate (probability of transmission) of VHS is about.5% when females carrying the wild-type gene (G) are involved

Im not sure if its addition/subtraction or multiplication.

VHS is about .5% and being heterozygous reduces that by 10%.
So is it just: .5%(1 - .10) = .45% ?

Thanks!

2. Originally Posted by hydride
What is the probability that reproduction will lead to the transmission of VHS from an infected male to an uninfected female that is heterozygous for the mutant allele?

Note: Use facts
#1:heterozygous (Gg) for mutation reduces the transmission rate of VHS by 10%
#4: transmission rate (probability of transmission) of VHS is about.5% when females carrying the wild-type gene (G) are involved

Im not sure if its addition/subtraction or multiplication.

VHS is about .5% and being heterozygous reduces that by 10%.
So is it just: .5%(1 - .10) = .45% ?

Thanks!
Seems correct to me! It's multiplication. You add when you're interested in several outcomes, that are part of the same sample space. For instance, what's the probability to get 1 or 2 when you throw a dice? The sample space is [1,2,3,4,5,6], so you need to add the individual probabilities (they are part of the same sample space). But when you're talking about probabilities that depend on each other, you need to multiply.

For example: An archer gets nervous when missing the first shot out of two. For the first shot, P(hit)=0,9, if he hits, P(hit) will remain the same. But if he misses, for the second shot P(hit) will be 0,8. What is the probability that he misses both?

Hope that you see the difference!