English Springer Spaniel Field Trial Association

AKC Parent Club of the Breed

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Recessive Gene Inheritance Patterns
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PARENTS OFFSPRING Expected average results based on at least 16 puppies.
genetic NORMAL genetic NORMAL genetic NORMAL genetic NORMAL genetic NORMAL genetic NORMAL Both parents are NORMAL . . . not carrying the recessive gene. 100% of the offspring will be NORMAL.
genetic NORMAL genetic CARRIER genetic NORMAL genetic NORMAL genetic CARRIER genetic CARRIER One parent is NORMAL; one parent is a CARRIER of the recessive gene . . . 50% of the offspring will be NORMAL and 50% will be CARRIERS. In PRA and RD, carriers can not be detected easily, thus pedigree analysis is critical.
genetic CARRIER AFFECTED genetic CARRIER genetic CARRIER AFFECTED AFFECTED An AFFECTED parent will aslways produce CARRIER offspring. In this situation, only 50% will be AFFECTED but the other 50% will be CARRIERS. Affected individuals used for breeding automatically identify their offspring as CARRIERS.
genetic CARRIER genetic CARRIER genetic NORMAL genetic CARRIER genetic CARRIER AFFECTED CARRIER to CARRIER breedings will produce 25% AFFECTED offspring, 25% NORMAL offspring, and 50% CARRIER offspring. In PRA and RD, the identification of the different offspring's genetic make-up is extremely complex.
genetic NORMAL AFFECTED genetic CARRIER genetic CARRIER genetic CARRIER genetic CARRIER An AFFECTED parent will produce only AFFECTED and CARRIER offspring. AFFECTED parent bred to a NORMAL parent will not produce any AFFECTED offspring, but all will be CARRIERS.
AFFECTED AFFECTED AFFECTED AFFECTED AFFECTED AFFECTED An AFFECTED parent bred to another AFFECTED parent will always produce 100% AFFECTED offspring.
genetic NORMAL  genetic NORMAL
genetic CARRIER  genetic CARRIER
AFFECTED  AFFECTED 		These are the only six possibilities of mating. Each of our dogs is the product of one of these six breeding combinations. Both PRA (Progressive Retinal Atrophy) and RD (Retinal Dysplasia) are accepted as recessive genes. This chart can be applied to the genetic inheritance pattern of both diseases. Produced by the Genetics and Health Education Committee of the English Springer Spaniel Field Trial Association, Inc.
 

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