“Draw a three-generation Angus pedigree for Curly Calf Syndrome, an autosomal recessive arthrogryposis multiplex condition, with carrier parents, an affected male proband, and an affected offspring from the proband mated to a carrier female.”
Comprenez les décisions qui le sous-tendent.
Both generation-I parents are carriers, making their affected son genetically possible.
The generation-II proband is affected and therefore carries two disease alleles.
The proband is mated to a carrier female, allowing an affected generation-III calf.
The unaffected sibling is not labeled a carrier because carrier status is not established by phenotype alone.
Use this educational pedigree to explain recessive inheritance and why verified DNA testing matters. Actual breeding decisions should use laboratory results and breed-association guidance.
Questions fréquentes
Is Curly Calf Syndrome recessive?
Yes. Arthrogryposis multiplex, commonly called Curly Calf Syndrome in Angus, is inherited as an autosomal recessive condition.
Why are both generation-I parents carriers?
An affected offspring must receive a disease allele from each parent, so two phenotypically normal parents must both be carriers in this example.
Can an unaffected animal still be a carrier?
Yes. A carrier has one disease allele and may be clinically unaffected, so DNA testing is needed to establish status.