Genetics question

[Newbie90]

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On the planet CCR, there is a recessive condition known as
Jambalaya. People with this trait have an uncontrollable
urge to Rock-n-Roll. The two alleles at the trait locus are
labeled R (trait) and r (wild type).



Problem 1. If the probability of transmitting an r allele is 0.44,
then what is the probability that any child born to carrier
parents will be affected (i.e., will rock!)?


Is this the same thing as probability of finding (RR)? if so would it be
P (RR) = 0.56 * 0.56 = .31


wild type means normal correct? (not have the disease) so that would be Rr or rr?
I know that recessive alleles are normally shown by two small letters but in this case it is not?

thanks.

 

[carlfusco]

The language is a little misleading, using a double entendre for the phrase "wild type." I think all they're asking is the probability of having a mutant or homozygous recessive offspring, which would just be .44*.44=.19. Yes, wild type generally refers to the dominant trait, as seen most often in the "wild."

 

[finchy86]

Is this the same thing as probability of finding (RR)? if so would it be
P (RR) = 0.56 * 0.56 = .31

wild type means normal correct? (not have the disease) so that would be Rr or rr?
I know that recessive alleles are normally shown by two small letters but in this case it is not?

thanks.

The language is misleading because it seems the R and r have been switched, but it really doesn't matter.

Carrier parents infers that they have the recessive allele, but also the dominant allele. So that means their genotype would be Rr. I think you did the work correctly.

 

[Newbie90]

The language is misleading because it seems the R and r have been switched, but it really doesn't matter.

Carrier parents infers that they have the recessive allele, but also the dominant allele. So that means their genotype would be Rr. I think you did the work correctly.

If the mutant gene is represented by the genotype (RR) wouldn't my original answer be correct? I know that normally a recessive gene is shown by two small letters (rr) but in this case my TA said that the RR genotype is the mutant one.

If I am correct that means the probability of NOT getting the disease would be the sum of the probability of Rr and rr correct?

 

[finchy86]

If the mutant gene is represented by the genotype (RR) wouldn't my original answer be correct? I know that normally a recessive gene is shown by two small letters (rr) but in this case my TA said that the RR genotype is the mutant one.

If I am correct that means the probability of NOT getting the disease would be the sum of the probability of Rr and rr correct?

I believe your original answer is correct. And yes, 1 - 0.31 is the probability of not being affected...or p^2+2pq