Deutsch
Hrvatski
Русский
Português
Amelogenesis Imperfecta Italian Greyhound Type
| Acronym: | AI, FEH |
| Gene: | ENAM |
| Mutation: | c.1991_1995delTTTCC |
| Inheritance: | Autosomal recessive |
| Sample type: | CHS (Cheek Swab), WBE (Whole Blood EDTA) |
Genetics and characteristics
Amelogenesis Imperfecta Italian Greyhound type is a congenital teeth disorder also known as enamel hypoplasia in Italian Greyhounds. The disorder has a strong resemblance to non-syndromic autosomal recessive amelogenesis imperfecta (AI) in humans. Tooth enamel makes most of the tooth tissue among humans and animals. It is a highly mineralized substance that has a role of a barrier to protect the tooth. In healthy teeth. Enamel is prone to degradation when exposed to acids from food and drinks. Amelogenesis Imperfecta in Italian Greyhound is affecting deciduous and permanent teeth and is manifested by enamel thinning and roughening or brownish mottling in areas of enamel thinning. It starts to develop in the early adulthood of the dog. The teeth that are affected appear to be small and pointed with increased gaps. While amelogenesis imperfecta causes cavities in humans, this condition does not occur in dogs, due to maintaining basic tooth structure throughout life. The disorder does not affect any tissues or organs other than teeth. Common symptoms occurring in Amelogenesis Imperfecta affected dogs are fever, nutritional disorders, trauma, or infection.
Amelogenesis Imperfecta Italian Greyhound type is caused by a mutation in the enamelin (ENAM) gene. The mutation comprises a 5-bp deletion in exon 10 of the named gene. This mutation causes the production of malfunctioning enamel proteins, such as amelogenin, enamelin, enamelysin, and kallikrein-4. AI is inherited in an autosomal recessive pattern. Healthy parents of an affected puppy are obligate heterozygotes and therefore carry one mutant allele. Heterozygotes have no symptoms. Dogs homozygous for the mutation will display the symptoms of the amelogenesis imperfecta. At conception, each cub has a 25% chance of being affected, a 50% chance of being an asymptomatic carrier, and a 25% chance of being unaffected and not a carrier. The recently conducted research has revealed a high carrier rate as well as a high occurrence of affected dogs. While approximately half of the dogs are unaffected (56%), 30% are carriers of the gene for amelogenesis imperfecta, and 14% of the dogs are affected.
Results Reported As
Test Result |
Interpretation of test result |
CLEAR |
Tested mutation was not detected in animal with „clear“ result. Animal tested as clear has wild-type allele in homozygous state (i.e. two pairs of healthy alleles). It will not develop disease caused by tested mutation.* It will pass only wild-type allele to its offspring. |
CARRIER |
Tested mutation was detected in animal with „carrier“ result. Animal tested as carrier has one wild-type and one mutation allele, it is in heterozygous state. It will not develop disease caused by tested mutation.* It can pass wild-type or mutation allele to its offspring. |
AFFECTED |
Tested mutation was detected in animal with „affected“ result. Animal tested as affected has two copies of mutation alleles affecting the gene. It is likely the animal will experience a genetic disorder due to this mutation.** It will pass only mutation allele to its offspring. |
*Test excludes only tested mutation but not possible unknown mutations or factors that can lead to similar condition/symptoms.
** Potential unknown mutations or multiple other factors can possibly affect the likelihood of experiencing a genetic disorder.
References:
Gandolfi B, Liu H, Griffioen L, Pedersen NC. Simple recessive mutation in ENAM is associated with amelogenesis imperfecta in Italian greyhounds. Anim Genet. 2013 Aug;44(5):569-78.