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mroquesi · 11-13-2009, 04:56 AM

Gess I have pushed some buttons here...
I like to reed the forum and learn new things.
If I heard someone crossed 2 blues and got a single one normal well,that would be something new, it would go against genetic laws about recessive genes.

First things first:
To be into breeding it is advisable to have at least an idea about genetics and about inheritance traits mechanisms.
I leave you a book, a 'bible' for any YTbreeder, I got it used from Amazon, assume most of you already read it:

"The joy of breeding your own show dog" by Anne Seranne, includes all the genetic concepts to retain if interested in breeding.

-Kdahmean:"I hate it when people who have never had a blue pup or seen one always has something negative to say"
Well, I DO have seen born in my hands and in my house 2blues, in a 4litter(50%) from 100%normal parents-older than 3years- so, evidence shows and science confirms my suspicion it is a

AUTOSOMAL RECESSIVE INHERITANCE, period.
If it was a dominat gene from just 1parent,he had to show the disease, but 2parents were and are normal, born black/tan.

"It is thought that Color Dilution Alopecia (CDA) is based on autossomal recessive gene transmission" [2].

Meaning :BOTH parents needed. and Not all pups will have to be carriers.

-MajesticYorkies:I have never seen a men walk on the moon with my eyes and I still believe he went there, I have never seen a gene or a chromosome and I do believe they exist.

Forgive me for believing it is possible to produce healthy purebred dogs that can be true to

the standard and win at shows.It just costs more because more dogs will have to be cut out of

breeding programmes, it's a more difficult job but the result would worth while.

I also know there are worse genetic defects than CDA, causing pain not only in future generations, and sometimes people choose to forgive health in face of beauty as a inevitable(?)price to pay.

Please reed page 913 Muller&Kirk's small animal dermatology, chapter congenital and hereditary defects, it talks about recessive traits and, more important, about how breeding apparently normal parents or siblings of an affected dog distributes the gene more widely, and advice to

avoid breeding OF ALL close relatives to the affected animal.

There are various degrees of this disease as in any other genetic condition. The genes involved are quite well determined and identified:

OMIA - Online Mendelian Inheritance in Animals

'The dilution gene -d especially the allele called -d1 may play an important role in the genetic transmission of color-mutant alopecia [1].'

Recently, evidence was provided that CDA is caused by one or more mutations within or near the MLPH gene(Philipp et al.2005)

Not all blues d/d diluted dogs have CDA and not all dogs that have
symptoms develop them at a similar age of onset or with
similar severity (3)

Black Hair Folicular Displasia-BHFD-and CDA probably origins from a ectodermal defect associated with MLPH gene (4).
Currently, most literature supports the theory that the 2 lesions are manifestations of the same disease (6,7).
CDA is a form of hair follicle dysplasia.

In YT with CDA condition I have seen, puppies born grey, not black.

Some interesting sites as you asked:

Polymorphisms within the canine MLPH gene are associated with dilute coat color in dogs

the melanophilin gene, linked to defects in some breeds, is one of 3 genes that occur at the "d"locus.

Alopecia, colour mutant in dog. OMIA Result

A noncoding melanophilin gene (MLPH) SNP at the splice donor of exon I represents a candidate causal mutation for coat color dilution in dogs

http://www.vetsci.org/2005/pdf/259.pdf ,from journal of veterinary cience.

Blue Dogs (Dog with a Blue Coat Color)

Wiley InterScience :: Session Cookies

in this abstract mind the words:'study of the pedigree proved autossomal recessive inheritance'!

"L’étude de L. Beco (BECO, FONTAINE et al. 1996) a permis, par étude d’une
lignée de chiens, de mettre en évidence le caractère autosomique récessif de
l’affection, au moins chez le Teckel. Ce caractère avait déjà été suspecté dans d’autres races, sans être véritablement prouvé (SELMANOWITZ,
MARKOFSKY et al. 1977;MILLER 1990; GUAGUERE 1991; HARGIS, BRIGNAC et al. 1991; MATHET et SEGAULT 1995)"(5)

interesting to reed also in(5) page 142:'maladie des oreilles de cuir chez le YT'not so rare as he described, to my knowledge.

Color dilution alopecia in a blue Doberman pinscher crossbreed

http://theses.vet-alfort.fr/telecharger.php?id=417 see table 61: Race de
chien/maladie/déterminisme génétique:autossomique récessif....voilá!again, and again recessive inheritance is described=2 parents needed.

(1)Miller WH. Colour dilution alopecia in Doberman Pinschers
with blue or fawn coat colours: A study of the incidence and
histopathology of this disorder. Vet Dermatol 1990,1,113-122.
(2)Beco L, Fontaine J, Gross TL, Charlier G. Colour dilution
alopecia in seven Dachshunds. A clinical study and the
hereditary, microscopical and ultrastructural aspect of the
disease. Vet Dermatol 1995.
(3)Wiley InterScience :: Session Cookies
(4)http://www.anclivepa-rs.com.br/artigos/dispasia.pdf
(5)Levy Fabien,these présentée à l'Univ.Claude-Bernard-Lyon I 2005 Les genodermatoses de l'epiderme, de la jonction dermo-epidermique et des annexes folliculaires du chien.
(6) Beco L, Fontaine J, Gross TL, Charlier G. Colour dilution alopecia in seven Dachshunds. A clinical study and the hereditary, microscopical and ultrastructural aspect of the disease. Vet Dermatol. 1996;7:91–97.
(7)Gross TL, Ihrke PJ, Walder EJ. Veterinary Dermatopathology: A Macroscopic and Microscopic Evaluation of Canine and Feline Skin Disease . St Louis: Mosby Year Book; 1992. pp. 298–302.

-Kdahmean:The site DPCA Breeders Education refers"Weimeraners as a breed are dd, all individuals are dilute, yet the disease is unreported in this breed."

I desagree: Just take a look at book 'Hair loss disorders in domestic animals'by Lars Mecklenburg pages 108-109 and you will see weimaraners do have CDA in a less severe form, findings are almost identical to CDA except milder.
DPCA Breeders refers: "In dilute individuals with normal appearing coats, these macromelanosomes are not grouped or clumped and cause no distortion of the cuticle (outer covering) of the hair."
I disagree: look page 142 in book'Small animal dermatology'by Anita Patel and book 'muller&kirk's small animal dermatology 967 .coat color dilution is based on irregular distribution of melanossomes in the hair shaft.All dilute color hairs contain larger than normal accumulations of melanin, cda or no cda.The pigment clumping in dilute hair leads to dilute colors or washed.Clumped melanin is visible in normal color dilute dogs.
The dilute hairs are lighter in color but contain as much or more melanin than the non dilute.
Cuticular defects were detected in normal and affected hairs from Yorkshire terriers, suggesting dilution genes express differently in different breeds.(Scott D.W. et al 2001).
The use of the word Macromelanossomes is considered 'impropre'.
The new suspected d1 allele must be RECESSIVE-again- to d, only d1d1 dogs will have cda(page78-82 these nº64 presentée à lúniversitée claude bernard-lyon 2003 les genodermatoses responsables
de troubles de la pigmentation,Maxime Decourt).

Hope I contributed to support my opinion and show new interesting sites.

11-13-2009, 04:56 AM	#121
mroquesi Yorkie Yakker Join Date: Jun 2005 Posts: 32	blue I believe blue yorkies are made of recessive genes from both parents Gess I have pushed some buttons here... I like to reed the forum and learn new things. If I heard someone crossed 2 blues and got a single one normal well,that would be something new, it would go against genetic laws about recessive genes. First things first: To be into breeding it is advisable to have at least an idea about genetics and about inheritance traits mechanisms. I leave you a book, a 'bible' for any YTbreeder, I got it used from Amazon, assume most of you already read it: "The joy of breeding your own show dog" by Anne Seranne, includes all the genetic concepts to retain if interested in breeding. -Kdahmean:"I hate it when people who have never had a blue pup or seen one always has something negative to say" Well, I DO have seen born in my hands and in my house 2blues, in a 4litter(50%) from 100%normal parents-older than 3years- so, evidence shows and science confirms my suspicion it is a AUTOSOMAL RECESSIVE INHERITANCE, period. If it was a dominat gene from just 1parent,he had to show the disease, but 2parents were and are normal, born black/tan. "It is thought that Color Dilution Alopecia (CDA) is based on autossomal recessive gene transmission" [2]. Meaning :BOTH parents needed. and Not all pups will have to be carriers. -MajesticYorkies:I have never seen a men walk on the moon with my eyes and I still believe he went there, I have never seen a gene or a chromosome and I do believe they exist. Forgive me for believing it is possible to produce healthy purebred dogs that can be true to the standard and win at shows.It just costs more because more dogs will have to be cut out of breeding programmes, it's a more difficult job but the result would worth while. I also know there are worse genetic defects than CDA, causing pain not only in future generations, and sometimes people choose to forgive health in face of beauty as a inevitable(?)price to pay. Please reed page 913 Muller&Kirk's small animal dermatology, chapter congenital and hereditary defects, it talks about recessive traits and, more important, about how breeding apparently normal parents or siblings of an affected dog distributes the gene more widely, and advice to avoid breeding OF ALL close relatives to the affected animal. There are various degrees of this disease as in any other genetic condition. The genes involved are quite well determined and identified: OMIA - Online Mendelian Inheritance in Animals 'The dilution gene -d especially the allele called -d1 may play an important role in the genetic transmission of color-mutant alopecia [1].' Recently, evidence was provided that CDA is caused by one or more mutations within or near the MLPH gene(Philipp et al.2005) Not all blues d/d diluted dogs have CDA and not all dogs that have symptoms develop them at a similar age of onset or with similar severity (3) Black Hair Folicular Displasia-BHFD-and CDA probably origins from a ectodermal defect associated with MLPH gene (4). Currently, most literature supports the theory that the 2 lesions are manifestations of the same disease (6,7). CDA is a form of hair follicle dysplasia. In YT with CDA condition I have seen, puppies born grey, not black. Some interesting sites as you asked: Polymorphisms within the canine MLPH gene are associated with dilute coat color in dogs the melanophilin gene, linked to defects in some breeds, is one of 3 genes that occur at the "d"locus. Alopecia, colour mutant in dog. OMIA Result A noncoding melanophilin gene (MLPH) SNP at the splice donor of exon I represents a candidate causal mutation for coat color dilution in dogs http://www.vetsci.org/2005/pdf/259.pdf ,from journal of veterinary cience. Blue Dogs (Dog with a Blue Coat Color) Wiley InterScience :: Session Cookies in this abstract mind the words:'study of the pedigree proved autossomal recessive inheritance'! "L’étude de L. Beco (BECO, FONTAINE et al. 1996) a permis, par étude d’une lignée de chiens, de mettre en évidence le caractère autosomique récessif de l’affection, au moins chez le Teckel. Ce caractère avait déjà été suspecté dans d’autres races, sans être véritablement prouvé (SELMANOWITZ, MARKOFSKY et al. 1977;MILLER 1990; GUAGUERE 1991; HARGIS, BRIGNAC et al. 1991; MATHET et SEGAULT 1995)"(5) interesting to reed also in(5) page 142:'maladie des oreilles de cuir chez le YT'not so rare as he described, to my knowledge. Color dilution alopecia in a blue Doberman pinscher crossbreed http://theses.vet-alfort.fr/telecharger.php?id=417 see table 61: Race de chien/maladie/déterminisme génétique:autossomique récessif....voilá!again, and again recessive inheritance is described=2 parents needed. (1)Miller WH. Colour dilution alopecia in Doberman Pinschers with blue or fawn coat colours: A study of the incidence and histopathology of this disorder. Vet Dermatol 1990,1,113-122. (2)Beco L, Fontaine J, Gross TL, Charlier G. Colour dilution alopecia in seven Dachshunds. A clinical study and the hereditary, microscopical and ultrastructural aspect of the disease. Vet Dermatol 1995. (3)Wiley InterScience :: Session Cookies (4)http://www.anclivepa-rs.com.br/artigos/dispasia.pdf (5)Levy Fabien,these présentée à l'Univ.Claude-Bernard-Lyon I 2005 Les genodermatoses de l'epiderme, de la jonction dermo-epidermique et des annexes folliculaires du chien. (6) Beco L, Fontaine J, Gross TL, Charlier G. Colour dilution alopecia in seven Dachshunds. A clinical study and the hereditary, microscopical and ultrastructural aspect of the disease. Vet Dermatol. 1996;7:91–97. (7)Gross TL, Ihrke PJ, Walder EJ. Veterinary Dermatopathology: A Macroscopic and Microscopic Evaluation of Canine and Feline Skin Disease . St Louis: Mosby Year Book; 1992. pp. 298–302. -Kdahmean:The site DPCA Breeders Education refers"Weimeraners as a breed are dd, all individuals are dilute, yet the disease is unreported in this breed." I desagree: Just take a look at book 'Hair loss disorders in domestic animals'by Lars Mecklenburg pages 108-109 and you will see weimaraners do have CDA in a less severe form, findings are almost identical to CDA except milder. DPCA Breeders refers: "In dilute individuals with normal appearing coats, these macromelanosomes are not grouped or clumped and cause no distortion of the cuticle (outer covering) of the hair." I disagree: look page 142 in book'Small animal dermatology'by Anita Patel and book 'muller&kirk's small animal dermatology 967 .coat color dilution is based on irregular distribution of melanossomes in the hair shaft.All dilute color hairs contain larger than normal accumulations of melanin, cda or no cda.The pigment clumping in dilute hair leads to dilute colors or washed.Clumped melanin is visible in normal color dilute dogs. The dilute hairs are lighter in color but contain as much or more melanin than the non dilute. Cuticular defects were detected in normal and affected hairs from Yorkshire terriers, suggesting dilution genes express differently in different breeds.(Scott D.W. et al 2001). The use of the word Macromelanossomes is considered 'impropre'. The new suspected d1 allele must be RECESSIVE-again- to d, only d1d1 dogs will have cda(page78-82 these nº64 presentée à lúniversitée claude bernard-lyon 2003 les genodermatoses responsables de troubles de la pigmentation,Maxime Decourt). Hope I contributed to support my opinion and show new interesting sites.