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A missense mutation in the agouti signaling protein gene (ASIP) is associated with the no light points coat phenotype in donkeys.

Abitbol M, Legrand R, Tiret L - Genet. Sel. Evol. (2015)

Bottom Line: This variant results in a cysteine to arginine substitution at position 117 in the ASIP protein.Altogether, our results strongly support that the identified mutation is causative of the NLP phenotype.Thus, we propose to name the c.[349 T > C] allele in donkeys, the a(nlp) allele, which enlarges the panel of coat colour alleles in donkeys and ASIP recessive loss-of-function alleles in animals.

View Article: PubMed Central - PubMed

Affiliation: Inra, Unité de Génétique Fonctionnelle et Médicale, Ecole nationale vétérinaire d'Alfort, Maisons-Alfort, 94700, France. m.abitbol@vet-alfort.fr.

ABSTRACT

Background: Seven donkey breeds are recognized by the French studbook and are characterized by a black, bay or grey coat colour including light cream-to-white points (LP). Occasionally, Normand bay donkeys give birth to dark foals that lack LP and display the no light points (NLP) pattern. This pattern is more frequent and officially recognized in American miniature donkeys. The LP (or pangare) phenotype resembles that of the light bellied agouti pattern in mouse, while the NLP pattern resembles that of the mammalian recessive black phenotype; both phenotypes are associated with the agouti signaling protein gene (ASIP).

Findings: We used a panel of 127 donkeys to identify a recessive missense c.349 T > C variant in ASIP that was shown to be in complete association with the NLP phenotype. This variant results in a cysteine to arginine substitution at position 117 in the ASIP protein. This cysteine is highly-conserved among vertebrate ASIP proteins and was previously shown by mutagenesis experiments to lie within a functional site. Altogether, our results strongly support that the identified mutation is causative of the NLP phenotype.

Conclusions: Thus, we propose to name the c.[349 T > C] allele in donkeys, the a(nlp) allele, which enlarges the panel of coat colour alleles in donkeys and ASIP recessive loss-of-function alleles in animals.

No MeSH data available.


No light points phenotype in donkeys. Most coloured donkeys show a light cream to white coat on their belly and around their eyes and muzzle (Normand donkey, left). Bay Normand donkeys occasionally give birth to no light points (NLP) donkeys that are not officially recognized by the studbook (NLP donkeys, middle). The NLP phenotype is recognized in American miniature donkeys (NLP American miniature donkey, right).
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Fig1: No light points phenotype in donkeys. Most coloured donkeys show a light cream to white coat on their belly and around their eyes and muzzle (Normand donkey, left). Bay Normand donkeys occasionally give birth to no light points (NLP) donkeys that are not officially recognized by the studbook (NLP donkeys, middle). The NLP phenotype is recognized in American miniature donkeys (NLP American miniature donkey, right).

Mentions: Mutations in the gene ASIP (agouti signaling protein) result in various coat patterns in domestic mammals (http://omia.angis.org.au) including mouse (www.informatics.jax.org), dog [1], cat [2], rabbit [3], horse [4], sheep [5-8], rat [9] and alpaca [10]. Only a few coat colours, patterns and textures have been described in domestic donkeys (Equus asinus). In donkeys, the coat colour can be white or coloured, i.e. black, bay, grey and red with or without white spotting; hair texture is variable and includes the longhair phenotype, in addition to the common shorthair phenotype. Recently, we started to investigate the molecular aetiology of these phenotypes and identified three underlying loss-of-function mutations in the MC1R (melanocortin 1 receptor) and FGF5 (fibroblast growth factor) genes that are responsible respectively, for the red colour and longhair phenotype in donkeys [11,12]. Most coloured donkeys are born with a pangare or light points (LP) pattern that associates cream to grey-white hair on the belly, around the muzzle and around the eyes. In the American miniature donkey breed, all coat colours and patterns are admissible and foals with a no light points (NLP) coat are often obtained from LP breeding stock (Figure 1). This has led breeders to suspect a recessive inheritance pattern for the NLP pattern. For the seven French donkey breeds (Pyrenean, Berry Black, Poitou, Cotentin, Provence, Bourbonnais and Normand), the NLP pattern is not officially recognized. However, dark NLP donkeys are occasionally born to bay Normand parents (Figure 1).Figure 1


A missense mutation in the agouti signaling protein gene (ASIP) is associated with the no light points coat phenotype in donkeys.

Abitbol M, Legrand R, Tiret L - Genet. Sel. Evol. (2015)

No light points phenotype in donkeys. Most coloured donkeys show a light cream to white coat on their belly and around their eyes and muzzle (Normand donkey, left). Bay Normand donkeys occasionally give birth to no light points (NLP) donkeys that are not officially recognized by the studbook (NLP donkeys, middle). The NLP phenotype is recognized in American miniature donkeys (NLP American miniature donkey, right).
© Copyright Policy - open-access
Related In: Results  -  Collection

License 1 - License 2
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getmorefigures.php?uid=PMC4389795&req=5

Fig1: No light points phenotype in donkeys. Most coloured donkeys show a light cream to white coat on their belly and around their eyes and muzzle (Normand donkey, left). Bay Normand donkeys occasionally give birth to no light points (NLP) donkeys that are not officially recognized by the studbook (NLP donkeys, middle). The NLP phenotype is recognized in American miniature donkeys (NLP American miniature donkey, right).
Mentions: Mutations in the gene ASIP (agouti signaling protein) result in various coat patterns in domestic mammals (http://omia.angis.org.au) including mouse (www.informatics.jax.org), dog [1], cat [2], rabbit [3], horse [4], sheep [5-8], rat [9] and alpaca [10]. Only a few coat colours, patterns and textures have been described in domestic donkeys (Equus asinus). In donkeys, the coat colour can be white or coloured, i.e. black, bay, grey and red with or without white spotting; hair texture is variable and includes the longhair phenotype, in addition to the common shorthair phenotype. Recently, we started to investigate the molecular aetiology of these phenotypes and identified three underlying loss-of-function mutations in the MC1R (melanocortin 1 receptor) and FGF5 (fibroblast growth factor) genes that are responsible respectively, for the red colour and longhair phenotype in donkeys [11,12]. Most coloured donkeys are born with a pangare or light points (LP) pattern that associates cream to grey-white hair on the belly, around the muzzle and around the eyes. In the American miniature donkey breed, all coat colours and patterns are admissible and foals with a no light points (NLP) coat are often obtained from LP breeding stock (Figure 1). This has led breeders to suspect a recessive inheritance pattern for the NLP pattern. For the seven French donkey breeds (Pyrenean, Berry Black, Poitou, Cotentin, Provence, Bourbonnais and Normand), the NLP pattern is not officially recognized. However, dark NLP donkeys are occasionally born to bay Normand parents (Figure 1).Figure 1

Bottom Line: This variant results in a cysteine to arginine substitution at position 117 in the ASIP protein.Altogether, our results strongly support that the identified mutation is causative of the NLP phenotype.Thus, we propose to name the c.[349 T > C] allele in donkeys, the a(nlp) allele, which enlarges the panel of coat colour alleles in donkeys and ASIP recessive loss-of-function alleles in animals.

View Article: PubMed Central - PubMed

Affiliation: Inra, Unité de Génétique Fonctionnelle et Médicale, Ecole nationale vétérinaire d'Alfort, Maisons-Alfort, 94700, France. m.abitbol@vet-alfort.fr.

ABSTRACT

Background: Seven donkey breeds are recognized by the French studbook and are characterized by a black, bay or grey coat colour including light cream-to-white points (LP). Occasionally, Normand bay donkeys give birth to dark foals that lack LP and display the no light points (NLP) pattern. This pattern is more frequent and officially recognized in American miniature donkeys. The LP (or pangare) phenotype resembles that of the light bellied agouti pattern in mouse, while the NLP pattern resembles that of the mammalian recessive black phenotype; both phenotypes are associated with the agouti signaling protein gene (ASIP).

Findings: We used a panel of 127 donkeys to identify a recessive missense c.349 T > C variant in ASIP that was shown to be in complete association with the NLP phenotype. This variant results in a cysteine to arginine substitution at position 117 in the ASIP protein. This cysteine is highly-conserved among vertebrate ASIP proteins and was previously shown by mutagenesis experiments to lie within a functional site. Altogether, our results strongly support that the identified mutation is causative of the NLP phenotype.

Conclusions: Thus, we propose to name the c.[349 T > C] allele in donkeys, the a(nlp) allele, which enlarges the panel of coat colour alleles in donkeys and ASIP recessive loss-of-function alleles in animals.

No MeSH data available.