SEARCH · Search PubMed

Results for “Hair Color”

Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.

SourceResearch connectionFrom yearThrough year

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 721 records · Page 40Linked to original sources

PubMedDate not supplied

Coat color genetics of Peromyscus. I. Ashiness, an age-dependent coat color mutation in the deer mouse.

Ashy deer mice (Peromyscus maniculatus) were first discovered about 1960 in a wild population from Oregon. Although indistinguishable from the wild type at weaning, ashy deer mice become progressively grayer with subsequent molts. The trait is inherited as an autosomal recessive and the symbol ahy is assigned for the locus. The trait is distinctly manifest by 6 months of age, at which time homozygotes have white hairs on the muzzle and at the base of the tail. The amount of white gradually increases with age, but development varies greatly among animals. Some become virtually all white by 18 months. Implants of melanocyte-stimulating hormone induced production of pigment in depigmented portions of the coat, indicating that viable melanocytes were present. The ashy deer mouse model may be useful for further study of melanocyte function.

Aging↗

PubMed1999

Close association between sequence polymorphism in the KIT gene and the roan coat color in horses.

The roan coat color in horses is controlled by a dominant allele that is lethal in the homozygous condition. Phenotypic similarities to some pigmentation disorders in human and mouse, combined with comparative mapping data, identified KIT, encoding the mast cell growth factor receptor, as a major candidate gene for the roan locus (Rn). Rn has previously been mapped to equine linkage group (LG) II. In this study, LGII was expanded with KIT and PDGFRA (platelet-derived growth factor receptor alpha) by use of RFLP and linkage analysis. Moreover, highly significant linkage disequilibrium between Rn and a KIT TaqI RFLP, representing a synonymous substitution in exon 19, was revealed. There was a strong KIT-Rn association in most breeds. Almost the complete KIT-encoding sequence was determined by sequence analysis of RT-PCR products. Comparison of horse KIT cDNA sequences, representing three different alleles (two different rn and one Rn), revealed five sequence polymorphisms and several mRNA splice variants, but none of these proved to be specifically associated with Rn. An insertion of a partial (79 bp) LINE1-element between exons 1 and 2, leading to a frameshift, represented about 30% of KIT transcripts in the Belgian roan horse used for the sequence analysis. However, an association between this L1 splice insertion and the roan phenotype was not verified when testing additional unrelated roan and non-roan horses from different breeds. The study strengthens the hypothesis that the roan coat color is controlled by KIT, but further analyses are needed to reveal the causative mutation(s).

Alternative Splicing↗

PubMed1984

Hormonal regulation of the annual pelage color cycle in the Djungarian hamster, Phodopus sungorus. I. Role of the gonads and pituitary.

The Djungarian hamster exhibits an agouti pelage in the summer and a predominantly white pelage in the winter. This pelage color cycle is known to be regulated by the length of the daily photoperiod probably acting through the pineal gland, as is the seasonal cycle of reproductive function with which it is closely correlated ( Figala et al., '73; Hoffmann, ' 78b ). The possibility of a causal relationship between the decline in gonadal hormone secretion and the coat color change occurring in short photoperiod was examined. Gonadectomized and intact male and female hamsters were exposed to either long (16L:8D) or short ( 10L : 14D ) photoperiod for several months. Gonadectomy neither induced the change to the winter pelage color in long photoperiod-housed animals, nor prevented either the change to the winter pelage or the spontaneous return to summer pelage color in short photoperiod-housed animals. Chronic implants of testosterone in castrated males delayed and attenuated the short photoperiod-induced coat color change. Administration of ovine prolactin (100 micrograms/day) stimulated pigmentation in hamsters with the winter pelage, whereas administration of a alpha MSH (30 micrograms/day) was without effect. These results suggest that changes in pelage color may be regulated largely by changes in pituitary prolactin secretion and modified to some extent by changes in gonadal steroid hormone secretion.

Animals↗

PubMed1997

The LEXF: a new set of rat recombinant inbred strains between LE/Stm and F344.

A new set of rat RI strains consisting of 11 independent strains and 13 of their substrains was established by inbreeding F2 rats between F344/DuCrj and LE/Stm. The strain distribution pattern was examined for 66 microsatellite loci, 8 biochemical genetic markers, 2 histocompatibility loci, and 2 coat color genes. A rat salivary protein gene Spe1 was newly mapped on Chr 1.

Alleles↗

PubMedDate not supplied

Hypervariable yellow (Ahvy), a new murine agouti mutation: Ahvy displays the largest variation in coat color phenotypes of all known agouti alleles.

A new coat color mutation, which occurred spontaneously in the C3H/HeJ strain, has been identified. The original C3H/HeJ male mouse carrying the mutation was unusual because its coat color appeared mostly yellow, in contrast to the wild-type agouti coat normally exhibited by mice of the C3H/HeJ strain. Genetic crosses showed that the mutant phenotype was inherited as a single autosomal dominant gene. The mutation was backcrossed onto a C57BL/6J background and tested for allelism with the agouti locus. The results showed that the mutation, named hypervariable yellow (Ahvy), is a new allele of the agouti locus. Ahvy is unique because mice carrying the mutation can display a range of coat color from pure yellow to almost pure black. The Ahvy mutation is responsible for the largest range of coat color phenotypes yet identified for any single agouti mutation.

Alleles↗

PubMed1998

[Coat color in dogs. 1: Basics of coat color genesis].

Within this brief review of literature the biochemical and physiological basics of coat colour genetics in the domestic dog are described. Parallels to the wildcolour of the wolf are shown, out of which the most of the today known colour-mutations developed. Furthermore the 10 most important of the today known coat color genloci are listed and some breed and nomenclature examples are also given. As the actual knowledge concerning the coat color inheritance is not able yet to explain some occurring coat colours and -combinations, an all-breed including nomenclature is not possible until today.

Animals↗

PubMed1993

Quantitative estimation of chimerism in mice using microsatellite markers.

An embryonic stem cell line was established from SV129 mouse blastocysts and used to generate chimeric mice by injection into OF1 blastocysts; 18 out of the 30 resulting offspring appeared chimeric as judged from their coat color patterns, and 3 of the 13 males proved to be germ-line chimeras as they transmitted the SV129 agouti phenotype to all or part of their offspring. The degree of chimerism of these males was evaluated for different tissues using polymorphic microsatellite markers amplified by the polymerase chain reaction. It was shown that these new markers can be effectively used to quantitatively estimate levels of chimerism. The CKMM (creatine kinase, muscle) microsatellite system was used to distinguish the SV129 from the OF1 genotype. In all performed tests, the correlation between DNA ratio and signal ratio, expressed as a base 10 logarithm, was shown to exceed or equal 0.98 for known DNA ratios (SV129/OF1) ranging from 1/99 to 99/1. Linear calibration methods were used to predict the % SV129 DNA of a test sample based on the obtained signal ratio. The accuracy of the prediction was evaluated by performing repeated measurements. Differences among three repeated estimates ranged from 2 to 17% for a given sample. Microsatellite systems should be very useful to monitor chimerism involving strains that can not be discerned with coat color or biochemical markers. This will be particularly important when ES methodology becomes available in species other than mice.

Animals↗

PubMedDate not supplied

Genome scan reveals new coat color loci in exotic pig cross.

The porcine genome was scanned to identify loci affecting coat color in an experimental cross between the Meishan breed and Dutch commercial lines. Linkage was studied in 1181 F(2) animals for 132 microsatellite markers and seven binary coat color scores: White, Black spotting, Speckle, Gray, Black, and specific color phenotypes for head and legs. The analyses were performed using interval mapping under various models. The study confirmed the existence of coat color loci on chromosome 8 and chromosome 6. One additional locus affecting White was detected on chromosome 5, possibly representing the porcine equivalent of the steel factor. Two new loci affecting Black were detected on chromosome 2. One of these showed exclusive maternal expression and mapped to a region where imprinted genes have been reported. The effect of the binary coding was tested by additional analyses excluding the white animals (>50% of F(2) animals). This showed that Black spotting was strongly influenced by the locus on chromosome 6 and the other color phenotypes were mainly influenced by the locus on chromosome 8. Epistatic effects were found between the loci on chromosomes 6 and 8 for Black spotting. For Black color, all combinations among chromosomes 2, 6, and 8 showed epistatic effects.

Animals↗

PubMedDate not supplied

A black-moorit mosaic-colored Icelandic ram.

A description is given of a black-moorit (black-chocolate brown) mosaic male lamb born in Iceland in the spring of 1982. A testmating resulted in 10 moorit and no black offspring from moorit dams. The results suggest that the mosaic color resulted from a mutation of the recessive allele b for moorit pigment to the dominant allele B for black pigment during fetal development, and that the mutation has not affected the gonadal tissue.

Animals↗

PubMed1995

Effects of solar radiation and wind speed on metabolic heat production by two mammals with contrasting coat colours.

We report the first empirical data describing the interactive effects of simultaneous changes in irradiance and convection on energy expenditure by live mammals. Whole-animal rates of solar heat gain and convective heat loss were measured for representatives of two ground squirrel species, Spermophilus lateralis and Spermophilus saturatus, that contrast in coloration. Radiative heat gain was quantified as the decrease in metabolic heat production caused by the animal's exposure to simulated solar radiation. Changes in convective heat loss were quantified as the variation in metabolic heat production caused by changes in wind speed. For both species, exposure to 780 W m-2 of simulated solar radiation significantly reduced metabolic heat production at all wind speeds measured. Reductions were greatest at lower wind speeds, reaching 42% in S. lateralis and 29% in S. saturatus. Solar heat gain, expressed per unit body surface area, did not differ significantly between the two species. This heat gain equalled 14-21% of the radiant energy intercepted by S. lateralis and 18-22% of that intercepted by S. saturatus. Body resistance, an index of animal insulation, declined by only 10% in S. saturatus and 13% in S. lateralis as wind speed increased from 0.5 to 4.0 ms-1. These data demonstrate that solar heat gain can be essentially constant, despite marked differences in animal coloration, and that variable exposure to wind and sunlight can have important consequences for both thermoregulatory stress experienced by animals and their patterns of energy allocation.

Animals↗

PubMed2005

[Effect study of white locus (I) on coat color inheritance in Chinese native pig breeds].

The classical White (I) locus is one of the important pig coat color hereditable loci,which is homologous to KIT gene. In this study,PCR-RFLP and PCR-SSCP analysis were commanded on the Intron 17 and 18 nucleotide sequences of KIT gene. The tested results showed that the substitution mutation (G-->A) of Intron 17 was found in white pigs, including Wuzhishan pigs (white), Landrace and Large White,and its genotype (AB) frequency was 1.1 and 0.8 respectively. The genotype frequency was uniformly 0 in the other native pig breeds. Similarly,the deleted mutation (AGTT) of Intron 18 was also found in the same white pigs,its genotype (,AA) frequency was 1.1 and 0.93 separately,while in the other native pig breeds was 0. Accordingly it was considered that KIT gene was an important factor regulating the white coat color genotype, and the classical I locus (KIT gene) was epistatic to the other genetic coat color loci. On the other hand,although the native pig breed Rongchang Pig is similar to Landrace and Large White in phenotype (white coat color), the mutation status found in them was absolutely distinct. So it is presumed that the coat color genetic system of Chinese native pig breeds was different from that of imported breeds.

Animals↗

PubMedDate not supplied

Male urinary protein-1 (MUP-1) in the rat: Mup-1 assigned to linkage group II.

A polymorphism was found in the electrophoretic mobilities of male-specific rat urinary proteins. The proteins (MUP-1) are inherited as a single autosomal trait. The Mup-1 locus possesses two codominant alleles Mup-1a (fast-migrating type) and Mup-1b (slowing migrating type). Mup-1 is closely linked to b (brown coat color), with a recombination frequency of 7.7 +/- 4.3 percent. The similarity to the linkage between Mup-1 and b in mice and rats is discussed.

Animals↗

PubMed2004

Dorsoventral patterning of the mouse coat by Tbx15.

Many members of the animal kingdom display coat or skin color differences along their dorsoventral axis. To determine the mechanisms that control regional differences in pigmentation, we have studied how a classical mouse mutation, droopy ear (de(H)), affects dorsoventral skin characteristics, especially those under control of the Agouti gene. Mice carrying the Agouti allele black-and-tan (a(t)) normally have a sharp boundary between dorsal black hair and yellow ventral hair; the de(H) mutation raises the pigmentation boundary, producing an apparent dorsal-to-ventral transformation. We identify a 216 kb deletion in de(H) that removes all but the first exon of the Tbx15 gene, whose embryonic expression in developing mesenchyme correlates with pigmentary and skeletal malformations observed in de(H)/de(H) animals. Construction of a targeted allele of Tbx15 confirmed that the de(H) phenotype was caused by Tbx15 loss of function. Early embryonic expression of Tbx15 in dorsal mesenchyme is complementary to Agouti expression in ventral mesenchyme; in the absence of Tbx15, expression of Agouti in both embryos and postnatal animals is displaced dorsally. Transplantation experiments demonstrate that positional identity of the skin with regard to dorsoventral pigmentation differences is acquired by E12.5, which is shortly after early embryonic expression of Tbx15. Fate-mapping studies show that the dorsoventral pigmentation boundary is not in register with a previously identified dermal cell lineage boundary, but rather with the limb dorsoventral boundary. Embryonic expression of Tbx15 in dorsolateral mesenchyme provides an instructional cue required to establish the future positional identity of dorsal dermis. These findings represent a novel role for T-box gene action in embryonic development, identify a previously unappreciated aspect of dorsoventral patterning that is widely represented in furred mammals, and provide insight into the mechanisms that underlie region-specific differences in body morphology.

Agouti Signaling Protein↗

PubMed1995

The role of melanocyte-stimulating hormone (MSH) receptor in bovine coat color determination.

The melanocyte-stimulating hormone (MSH) receptor has a major function in the regulation of black (eumelanin) versus red (phaeomelanin) pigment synthesis within melanocytes. We report three alleles of the MSH-receptor gene found in cattle. A point mutation in the dominant allele ED gives black coat color, whereas a frameshift mutation, producing a prematurely terminated receptor, in homozygous e/e animals, produces red coat color. The wild-type allele E+ produces a variety of colors, reflecting the possibilities for regulating the normal receptor. Microsatellite analysis, RFLP studies, and coat color information were used to localize the MSH-receptor to bovine Chromosome (Chr) 18.

Alleles↗

PubMed2002

[Horse breeding: genetic tests for the coat colors chestnut, bay and black. Results from a preliminary study in the Swiss Freiberger horse breed].

Coat color played an important role during domestication and formation of breeds. Livestock breeders often had special preferences for particular color phenotypes because they believed them to be associated with performance or fitness traits. Socio-cultural reasons might have had an influence on color selection as well. Recently genetic tests on DNA level got available to genotype in any individual horse for basic horse coat colors (chestnut, bay, black). In particular, hidden carriers of the recessive chestnut and black allele are recognizable with these tests. A sample of 162 Franches-Montagnes horses from Switzerland was genotyped for the alleles for chestnut and black. The analysis of allele frequencies revealed a high prevalence of the chestnut allele and a low frequency of the black allele in this population. Rare colors are in demand on the market. The statistical analysis of 1369 offspring from five stallions indicate, that darker shades of basic color phenotypes (dark chestnut, dark bay) follow a recessive mode of inheritance in the Franches-Montagnes horse breed.

Animals↗

PubMed2001

[Effect of four mutations (Cr,S,S(H),h) in genes for mink coat color on brain monoamine oxidase].

Activity of A and B types of monoamine oxidase (MAO) has been investigated in the brain stem and brain hemispheres of mink males of five genotypes for coat-color mutations: standard dark-brown (+/+); heterozygous for the semidominant mutation Black crystal (Cr/+); homozygous for the semidominant mutation Black cross, or "95% White" (S/S); heterozygous for the semidominant mutation Shadow (SH/+); and homozygous for the semirecessive mutation hedlum white (h/h). The main changes in the activity of the A and B MAO types occur in the brain hemispheres. A reduced activity of MAO A has been recorded in the hemispheres of Black crystal minks (Cr/+) and an elevated activity, in the hemispheres of Shadow (SH/+) and 95% White (S/S). The activity of MAO B is reduced in the hemispheres of Black crystal and elevated in the hemispheres of hedlum white (h/h). An increased MAO A activity has also been recorded in the brain stem of Shadow minks (SH/+). It is suggested that genes controlling coat color have a pleiotropic effect on sexual behavior in males and the endocrine function of testicles mediated by a putative change in the metabolism of brain neurotransmitters, substrates of MAOs A and B.

Animals↗

PubMed1986

Faded, a mutation in the KSB strain of mouse which shows age-related pigment changes.

Mice with a strange coat color were found in the KSB strain and separated as KSB-fe after fixation for this gene. These mutant mice have faded coat color (black becomes gray), with white underfur, the pigment changing towards white accompanied by frequent skin lesions. Faded homozygotes show a loss of pigment granules with ageing. Genetic studies were conducted with mice bearing this faded coat color. The mode of inheritance of the faded coat color was established to be autosomal recessive and the name faded (fe) was proposed. Faded was not allelic to dilute (d), leaden (ln), beige (bg) or pink-eyed dilution (p) loci.

Aging↗

PubMed2003

Genetic determinants of sable and umbrous coat color phenotypes in mice.

The dorsal fur in yellow F1 mice (F1-Ay) between C3H/HeJ and C57BL/6J-Ay is darker than that in C57BL/6J-Ay. Moreover, yellow F2 mice (F2-Ay) exhibit a wide spectrum of coat color phenotypes in terms of lightness and darkness. Quantitative trait locus (QTL) analysis on F2-Ay identified three significant modifier loci that accounted for darkening of the coat color on chromosomes 1 (Dmyaq1 and Dmyaq2) and 15 (Dmyaq3), and the C3H/HeJ allele at these loci increased the darkness. Because agouti F2 mice (F2-A) also exhibited a spectrum of coat color phenotypes, the question of whether these QTLs had any effects on F2-A was examined. Dmyaq1 and Dmyaq2 were shown to increase the darkness in F2-A, whereas Dmyaq3 did not. The results showed that Dmyaq1-Dmyaq3 were parts of determinants responsible for the sable (darker modification of yellow) coat color phenotype, and that Dmyaq1 and Dmyaq2 were parts of determinants responsible for the umbrous (darker modification of agouti) coat color phenotype. It is, thus, demonstrated that both the sable and the umbrous phenotypes resulted from multigenic contributions, and that they shared genetic bases, as had been implied for several decades.

Agouti Signaling Protein↗