ANBI 360.3 Lecture 10: lecture 10 360
20 Jun 2018
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LECTURE 10
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D locus = Melanophilin!
grey or "blue" in ~20 breeds co-segregates with mutation found in MLPH!•
mostly effect black dogs making them grey or blue!•
causes dilute expression of eumelanin and phaeomelanin!•
always had charcoal nose and pads!•
and both eumelanin pigments!•
"silver" labrador retriever pups are controversial!•
!
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Merle- PMEL!
has health ramifications!•
deaf ( homozygous merle) and microphthalmic (small eyes)!◦
more then one color in the iris of the eye in heterozygous!◦
SINE alone does not cause merle!•
TTTTT not found without SINE in merle dogs!•
merle dogs with out where sporting appear to have fewer side effects!•
merle is not visible on fawn/sable background color!•
e/e is epistatic to merle!•
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Harlequin Spotting!
one H and one M (merle) allele required!•
H/H is fetal lethal!•
unique to Great Dane thus far!•
has to be heterozygous to merle too!•
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White Spotting!
MITF has been reported to cause spotting in some breeds!•
one mutation is a SINE!•
spotting alleles!
little postulated 4 alleles:!•
S> s^i> s^P> s^W!•
but DNA data don't support all these!•
SINE acts as a recessive, not a co-dominance in some breeds!•
most breeds it acts as a complete recessive!•
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Whats as white extreme spotting?!
don't really understand why its white!
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Cream/White!
samoyeds are e/e and a/a/ so can produce neither pigment!•
a allele found only in herding breeds!•
can not produce pigment!•
haven't found another breed like this!•
in many breeds e/e dogs are cream to white instead of red!•
these dogs are fixed for a paling genotype, at a gene that is yet unknown!•
!
Roan and ticked!
has some health ramifications in:!•
Document Summary
Grey or blue in ~20 breeds co-segregates with mutation found in mlph mostly e ect black dogs making them grey or blue causes dilute expression of eumelanin and phaeomelanin always had charcoal nose and pads and both eumelanin pigments. Merle- pmel has health rami cations deaf ( homozygous merle) and microphthalmic (small eyes) more then one color in the iris of the eye in heterozygous. Ttttt not found without sine in merle dogs merle dogs with out where sporting appear to have fewer side e ects merle is not visible on fawn/sable background color e/e is epistatic to merle. Mitf has been reported to cause spotting in some breeds one mutation is a sine little postulated 4 alleles: S> s^i> s^p> s^w but dna data don"t support all these. Sine acts as a recessive, not a co-dominance in some breeds most breeds it acts as a complete recessive one h and one m (merle) allele required.
