Hey there! Sign in to join this conversationNew here? Join for free
    • Thread Starter
    Offline

    1
    ReputationRep:
    Hey, so I have been studying about lethal alleles in my genetics module.

    In the yellow mice cross, where the yellow is dominant but lethal if two alleles are obtained, why do we use Ay to represent the yellow allele (dominant) and just A to represent the darker coloured allele?

    Can't I use A to represent the yellow allele, which is dominant, and and small a to represent the darker coloured allele? Thanks.
    Offline

    10
    ReputationRep:
    No, because lower case a refers to a non-agouti allele which is separate. Both A and Ay give rise to agouti, and both are dominant alleles. It's almost like three tiers, homozygous recessive a produces a non-agouti mouse, homozygous dominant A produces an agouti/wild type mouse and heterozygous A/Ay gives rise to the yellow coat, and then AyAy is lethal. Hope this makes sense!
 
 
 
Poll
Who is your favourite TV detective?

The Student Room, Get Revising and Marked by Teachers are trading names of The Student Room Group Ltd.

Register Number: 04666380 (England and Wales), VAT No. 806 8067 22 Registered Office: International House, Queens Road, Brighton, BN1 3XE

Write a reply...
Reply
Hide
Reputation gems: You get these gems as you gain rep from other members for making good contributions and giving helpful advice.