Post by Aussienot on Sept 21, 2004 23:15:19 GMT -5
Anna Salleh
ABC Science Online
Monday, 20 September 2004
A stud's life is hard work: first a bar code, now a cheek swab and DNA test. Australian purebred dogs will soon need genetic identity papers to prove their pedigree and show if they carry the risk of hereditary diseases.
Only dogs used for breeding stock will need this genetic 'stud book'; and not purebred show dogs or the average pet poodle, according to the Australian National Kennel Council (ANKC).
Testing will be introduced in stages, before it becomes mandatory in January 2008.
The move towards genetic testing, which was made at the ANKC's recent annual conference in Sydney, is aimed at reducing the incidence of hereditary disease in purebreds.
"We're looking to improve future generations," said dog breeder Bob Maver, of the ANKC canine health committee. Because of their small gene pool, purebred dogs are particularly vulnerable to hereditary diseases, said Maver, who has been working on these diseases since 1988. The Australian Kelpie is the only ANKC registered dog breed which is not known to carry genetic diseases.
This is especially so as most diseases are recessive, which means two copies of a defective gene are needed for a dog to get the disease. If it only has one copy of a gene a dog will be a carrier, which can be a problem, especially for breeding stock.
Before the advent of genetic testing, parents of an affected dog would be excluded from breeding. But it was not possible to know if unaffected siblings of affected dogs were carriers.
"A dog had to produce an affected offspring to be known as a carrier and excluded from breeding," said Maver. "It was very hard to exclude the carriers [so a disease] could be handed down for generations and generations and all of a sudden pop up."
One hereditary liver-storage disease affecting border collies, effectively "sent the dogs mad", said Maver. Another blindness disease affecting Irish setters, called progressive retinal atrophy (PRA), is caused by the same gene that causes retinitis pigmentosa in humans.
Maver said that PRA in Irish setters had persisted despite an attempt to eradicate it in the 1950s.
"In England they had a major program to find the carriers and weed them out," he said. "They culled a huge number of dogs. They thought they'd got all the carriers but no, it's continued ever since."
He said a genetic test for the disease had been developed recently and could be included in the new genetic testing program.
"Genetic testing allows you to find the carriers," he said. "You can locate the actual genes and you can selectively breed to prevent the disease in just one generation."
DNA 'identity papers'
Under the new Australian Canine Pedigree Assurance Program, to be introduced over the next four years, the ANKC will require breeding dogs to have their DNA status on their stud book.
Each dog will have to have a DNA test from a cheek swab to confirm its identity and any defective genes it may carry. Barcodes on samples and dogs, using a microchip or tattoo, will be used to ensure there are no mix-ups.
Stud book registration will be recommended for male dogs and voluntary for bitches until January 2006, and mandatory for registration of new litters by January 2008. By 2008, all breeding stock will have to be registered and a dog will not be eligible for ANKC registration unless both its parents are registered.
The ANKC will carry out the program with Genetic Technologies Limited, which will train sample collectors and test the samples at its Melbourne labs. Genetic Technologies also plans to use stored DNA samples to develop new tests.
"My ambition has always been to eliminate these diseases from the dogs' point of view," said Maver. "We should not be breeding dogs that have diseases."
ABC Science Online
Monday, 20 September 2004
A stud's life is hard work: first a bar code, now a cheek swab and DNA test. Australian purebred dogs will soon need genetic identity papers to prove their pedigree and show if they carry the risk of hereditary diseases.
Only dogs used for breeding stock will need this genetic 'stud book'; and not purebred show dogs or the average pet poodle, according to the Australian National Kennel Council (ANKC).
Testing will be introduced in stages, before it becomes mandatory in January 2008.
The move towards genetic testing, which was made at the ANKC's recent annual conference in Sydney, is aimed at reducing the incidence of hereditary disease in purebreds.
"We're looking to improve future generations," said dog breeder Bob Maver, of the ANKC canine health committee. Because of their small gene pool, purebred dogs are particularly vulnerable to hereditary diseases, said Maver, who has been working on these diseases since 1988. The Australian Kelpie is the only ANKC registered dog breed which is not known to carry genetic diseases.
This is especially so as most diseases are recessive, which means two copies of a defective gene are needed for a dog to get the disease. If it only has one copy of a gene a dog will be a carrier, which can be a problem, especially for breeding stock.
Before the advent of genetic testing, parents of an affected dog would be excluded from breeding. But it was not possible to know if unaffected siblings of affected dogs were carriers.
"A dog had to produce an affected offspring to be known as a carrier and excluded from breeding," said Maver. "It was very hard to exclude the carriers [so a disease] could be handed down for generations and generations and all of a sudden pop up."
One hereditary liver-storage disease affecting border collies, effectively "sent the dogs mad", said Maver. Another blindness disease affecting Irish setters, called progressive retinal atrophy (PRA), is caused by the same gene that causes retinitis pigmentosa in humans.
Maver said that PRA in Irish setters had persisted despite an attempt to eradicate it in the 1950s.
"In England they had a major program to find the carriers and weed them out," he said. "They culled a huge number of dogs. They thought they'd got all the carriers but no, it's continued ever since."
He said a genetic test for the disease had been developed recently and could be included in the new genetic testing program.
"Genetic testing allows you to find the carriers," he said. "You can locate the actual genes and you can selectively breed to prevent the disease in just one generation."
DNA 'identity papers'
Under the new Australian Canine Pedigree Assurance Program, to be introduced over the next four years, the ANKC will require breeding dogs to have their DNA status on their stud book.
Each dog will have to have a DNA test from a cheek swab to confirm its identity and any defective genes it may carry. Barcodes on samples and dogs, using a microchip or tattoo, will be used to ensure there are no mix-ups.
Stud book registration will be recommended for male dogs and voluntary for bitches until January 2006, and mandatory for registration of new litters by January 2008. By 2008, all breeding stock will have to be registered and a dog will not be eligible for ANKC registration unless both its parents are registered.
The ANKC will carry out the program with Genetic Technologies Limited, which will train sample collectors and test the samples at its Melbourne labs. Genetic Technologies also plans to use stored DNA samples to develop new tests.
"My ambition has always been to eliminate these diseases from the dogs' point of view," said Maver. "We should not be breeding dogs that have diseases."