PHINEAS WHITING (1887 - 1978, GENETICIST)
Phineas Wescott Whiting was born in Lowell, Massachusetts in 1887 and died in February 1978. For cat fanciers, he was an important early geneticist, reliant on experimental breeding and observation, and his insights were little short of miraculous. He was interested in sex determination, colour variations and colour inheritance, and these interests came together in a series of papers about cats. Between 1912 and 1919, while at the universities of Harvard and Pennsylvania, he studied cats and wrote papers about the inheritance of tabby patterns, white spotting and tortoiseshell. The tortoiseshell cat was a conundrum because almost all were female, while the few males were often infertile or abnormal.
EARLY STUDIES
Phineas Whiting studied at both Dartmouth and Harvard. He achieved an Applied Biology degree in 1911 and a Master’s degree in Biology in 1922. He was particularly interested in insects and worked with William Morton Wheeler, entomologist and professor of applied biology at Harvard’s Bussey Institution. However, Whiting was interested in the role of genetics, while Wheeler was not. Whiting began to work instead with William Ernest Castle, a zoologist interested in Mendelian inheritance and the role of selection. They became part of a research group that included Clarence C. Little, Sewall Wright and Leslie C. Dunn. Whiting’s studies focused on coat colour inheritance in domestic cats and rats, and in colour variations in frogs and insects. In 1914 he began breeding cats to study colour inheritance, an interest for several years and he wrote several papers about this.
In 1915 – 1916, while studying for his PhD at the University of Pennsylvania he also worked at the Marine Biological Laboratory at Woods Hole, Massachusetts where he met and married fellow student Anna Rachel Young. Whiting was studying the genetics of a parasitic wasp called Habrobracon juglandis. This wasp was parthenogenic – fertilised (diploid) eggs developed into females while unfertilised (haploid) eggs developed into males. In 1918 he published his first paper on sex determination in this wasp and he worked with parasitic wasps for over 50 years.
Whiting held a series of short-term teaching positions until he was appointed research professor of eugenics at the Iowa Child Welfare Station attached to the University of Iowa in 1921. Anna Whiting began her own PhD work, switching from plant genetics to animal genetics and collaborating with her husband on some of his research projects. In 1921, Whiting’s friend and colleague from Harvard, Clarence C. Little, began research on dog behaviour at the Roscoe B. Jackson Memorial Laboratory. When Little’s dog study proved unproductive, the dogs were sold to the University of Iowa where Whiting and others set up a new dog behaviour project involving a physiologist, a psychologist, and a geneticist. This project was also abandoned.
EUGENICS AND SOCIALIST LEANINGS
Whiting published articles on eugenics, birth control, human heredity, and selection in socialist publications including “The Nation’s Health” and the “Birth Control Review.” He participated in the Sixth International Neo-Malthusian and Birth Control Conference, held in New York in March 1925, and his lecture, entitled “Selection, the Only Way of Eugenics,” was published in the “Birth Control Review.” While studying eugenics, Whiting wrote “Does alcohol affect the germ plasm injuriously, producing hereditary defects, or does it have a selective effect, as some of held, killing off the weaker germ cells and allowing only the better to survive? . . . In the former case it would be dysgenic, in the latter eugenic. Hence, is a reformed drunkard more eugenic, or less so than a man who has always been a total abstainer?” (Birth Control Review, August 1922)
In 1924, Anna completed her PhD and the couple moved to Orono, Maine where Whiting became professor of biology at the University of Maine in Sept 1924, head of the Dept of Biology in March 1925 and left in 1927. In 1927, the Whitings travelled to Berlin for the Fifth International Congress of Genetics, where they both presented papers. They then visited the Soviet Union and were impressed by the Soviet experiment in constructing a more egalitarian communist society. Between 1927 and 1929 the Whitings discovered that the parasitic wasps sometimes produced diploid males, feminised haploid males and even females with an extra set of chromosomes when normal females mated with diploid males. Some wasps were gynandromorphs - mosaics of male and female characteristics. At first, their reports and short papers were published locally in the Proceedings of the Pennsylvania Academy of Science or the Anatomical Record or Biological Bulletin.
In 1932, while professor at Pittsburgh, Whiting was dismissed due to the great depression, and partly due to his outspoken left-wing views. He continued to use the facilities at Woods Hole and at the Dept of Genetics at Cold Spring Harbor during 1934 and 1935, and in 1935 he became lecturer in Zoology at Pennsylvania University. In 1936 he became an associate professor. His work with parasitic wasps led him to postulate the X and Y factors in sex determination with females being XX and males being XY. By the 1940s he explained gynandromorph wasps (male-female mosaics) as coming from the fertilisation of eggs with 2 nuclei. His theories received support but were not generally accepted as the solution to sex determination.
In 1942, he was appointed full professor at Pennsylvania University and remained there until he retired from teaching in May 1953. Whiting was described by students as dedicated and conscientious with a contagious enthusiasm for genetics. In 1953, the Whitings moved to the Biological Division of the Oak Ridge National Laboratory where they continued their research. His studies into sex determination in wasps finally received recognition and were cited by other researchers.
CATS
Phineas Whiting extensively investigated the inheritance of colour in a series of breeding experiments starting in 1914 at the University of Pennsylvania. He also crossed his cats to Caffre cats owned by the Zoological Society of Philadelphia. He was methodical in crossing different patterns and colours of cats, meticulous in recording the results and his conclusions represent an early stage in understanding cat colour inheritance. His insights into cat coat colour inheritance were sometimes misinterpreted, partly due to the terminology he used to express his findings. These misinterpretations have been repeated in papers that referred to his findings.
Whiting used English terms to name genetic factors to avoid confusion with species names. He used the term 'mimic' to denote similar patterns occurring in different domestic animals e.g. piebaldism, and believed mimicry was due to the limited number of ways in which the mammalian coat could vary in dilution and distribution of the pigments black, brown, and yellow since “no other pigments can be developed.” He agreed with Metz (1916) that mimicry was probably due to homologous factors, even in widely separated species.
Whiting’s work on colour inheritance in cats built on that of L. Doncaster who had studied tortoiseshell cats and had concluded that orange was dominant over black in males, but only partially dominant over black in females (some of Doncaster’s data came from Whiting’s colleague, Dr. Little). Doncaster found the inheritance to be largely in accordance with simple sex-linkage, but believed that black, rather than yellow, was sex-linked. Although the Y chromosome was identified as a sex-determining chromosome in 1905, Whiting’s mentor, cytologist Clarence Erwin McClung, believed the X chromosome alone determined sex and it was not until the 1920s that the presence or absence of the Y chromosome was realised to determine sex.
WHITINGS DEDUCTIONS
Whiting made a number of deductions from his experiments and from data he gathered from others. Whiting’s breeding experiments at the University of Pennsylvania continued, but eczema (mange?) infected the breeding stock and his investigations ended due to the death of several animals.
He considered it unnecessary to try to trace variations in morphology and colour to one or other wild ancestor since the variations could occur under domestication. He considered the strictly domestic colour variations to be maltese (normal dilution), white, white-spotting, yellow, and Siamese dilution. He noted that such variations also occurred in other domestic animals and could 'mimic' each other. He noted that ticking factors and banding (striped pattern) factors occurred in both wild and domestic mammals and that domestic cats produced colour patterns similar to numerous wild species. Wild species had pattens comparable to silvering, extreme ticking and loss of agouti (melanism). He believed spots to be produced by intersecting longitudinal and transverse weaves of pigment-forming metabolic activity. In those respects he considered the domestic cat 'mimicked' its wild relatives, but left the question open as to whether those variations originated by crossing of wildcat species or by mutation in domestic cats.
Yellow, Black and Tortoiseshell
In his series of experiments at the University of Pennsylvania during 1914, Whiting investigated “the tortoiseshell problem” and along the way he described the dilution factor (gene) and the relationship between tabby and solid colour. He also realised that an apparently solid colour female cat, or one with just a few yellow hairs, was genetically tortoiseshell. He believed there were additional factors – “extension factors” - that produced a continuum of tortoiseshell ranging from solid yellow to solid black. That other factor, unknown at the time, would turn out to be random X-inactivation in females rather than a modifier gene.
Whiting realised that yellow, Y, was allelomorphic with black, y and was at a sex-linked locus, and postulated that the male was di-gametic for Y and y. He referred to tortoiseshell as “yellow spotting” and wrote that the tortoiseshell cat was the subject of much interest and discussion in relation to sex-correlated phenomena. Whiting had previously pointed out in 1915 that the hypothesis of simple sex linkage suggested by Little might be sufficient to account for the conditions if it be considered that the Yy heterozygotes, which must be females, varied from black through various degrees of yellow-spotting to solid yellow. He presumed conditions were much more stable in the male, as it was impossible to have a Yy heterozygote. Thus Whiting suggested that a gametically yellow male may become tortoiseshell by extreme selection of black extension factors, while a gametically black male may become tortoiseshell by an extreme selection of yellow extension factors. He did not exclude the possibility that a single factor or particular combination of factors could produce yellow-spotting in males.
Whiting suggested that the rare tortoiseshell male was either genetically yellow with an extreme of black extension factors or genetically black with an extreme of yellow extension factors. His hypothesis seemed plausible due to a small amount of evidence showing that male tortoiseshells bred as though they were yellows. He considered the sex-linkage to be absolute.
He also noted that the tabby factor that restricted black pigmentation and produced the tabby pattern, could produce tabby-torties, which might be misidentified as ordinary black-patterned tabbies. He suggested that white spots, which he knew to be inherited independently, might obscure either the yellow or the black patches on tortoiseshell females; this would lead to their colours being incorrectly recording and would skew the statistics.
Ticking and Tabbies
Whiting considered ticking (agouti) was due to at least 2 and probably more different factors. Black/non-agouti/uniformity (solid/self) was recessive to agouti, A. An extreme amount of ticking was presumed due to a third allelomorph in the series A1. Banding (tabby) was due to at least 2 and probably 3 different allelomorphs (B series) and the ticking factor revealed the lighter background colour. Less ticking meant more of the black pattern. He noted that the 3 banded patterns - lined, striped, and blotched - were distinct with no intermediates. Striped was separate from blotched and both were separate from solid black, and all could occur in the same litter. Within ticked cats, he noted various degrees of ticking ranging from light to heavy and called these “little ticked,” “much ticked” and “extremely ticked.”
Whiting divided the striped patterns into lined, striped and blotched. Lined cats were the Abyssinian-type cats with stripes very fine and close together, except on the legs, tail and nose, giving the impression of a uniformly agouti cat except for a dark vertebral line. He was unable to breed a non-agouti lined cat, but believed he could achieve this with the appropriate crosses. The lined, striped, and blotched patterns were fundamentally comparable, differing only in the width and distribution of coloured bands. He bred together blotched and striped tabbies and self coloured cats and the results were consistent with his assumption of 2 loci, one for the banding (tabby pattern) factors and one for the ticking factors. His natural assumption was that lined, striped, and blotched formed a triple allelomorphic series (were all at the same locus).
Dr. Charles Penrose, of Philadelphia, loaned Whiting his much-ticked lined male Caffre cat for crossing. Whiting demonstrated that the Caffre cat was genetically black. He also found that “lined” (Abyssinian pattern) was dominant to both striped and blotched and considered the patterns to all be at one locus..
His findings on banding (tabby pattern) were:
His findings on degrees of ticking were:
Interestingly, Whiting did not claim that tabby and ticking were an allelic series. He suggested it was a possibility, but in the same work he also suggested the possibility of two loci:
“The three types of banding - lined, striped, and blotched -, are each entirely distinct. No intergrades have been observed. The natural assumption is to suppose that they form a triple allelomorphic series, B1, B, and b, as I have tentatively assumed. But if two loci are involved the conditions might be expressed as follows: A lined cat might be LLBB, LLBb, LLbb, LlBB, LlBb, or Llbb. A striped cat might be llBB or llBb. A blotched cat would then be the double recessive, llbb. This scheme apparently fits the genetic data thus far collected. Striped and blotched would act as a pair of simple allelomorphs, B and b. The crosses involving the lined cats would be expressed by supposing that they are both of formula Llbb. Bred together they produced lined, LLbb or Llbb, and blotched, llbb. Crossed with blotched, either black or ticked, llbb, they give lined, Llbb, and blotched, llbb. Crossed with homoyzgous striped, llBB, they give lined, LIBb, and striped llBb.”
This second suggestion entirely corresponds to modern genetics but has been overlooked or misunderstood, probably because of terminology. “Ticking” is not now used in Whiting's sense, while "lined" actually means “ticked” in the modern sense.
Colour Dilution, Silvering and Siamese
Whiting found that intense pigmentation, M, was a simple dominant over dilute or maltese, m. Maltese dilution was a simple Mendelian recessive and not sex-linked.
He noted that pink-eyed albinism was not found in cats, but that it was possible that Siamese dilution represented an approach toward albinism.
Variations in the tone of colouration were extensive and formed a continuum. Silvers represented a reduction of both yellow and black pigment, and he considered smokes to be very dark silvers, not realising that smokes were non-agouti. The lighter bands of tabbies were straw- or cream-coloured, varying to white in silver tabbies and brown in brown tabbies. Occasionally the brown varied to a rusty red. Silver creams were yellow cats in which the yellow pigment was reduced to a minimum so that the hair sometimes appeared almost white. Whiting noted that, according to fanciers, silver tabbies bred together occasionally throw brown tabbies.
Silvering was a general reduction in the amount of yellow pigment so that the straw-colour bands of tabbies became white and black stripes alternated with white background. At the other extreme, some cats had a considerable amount of yellow pigment. He described a striped tabby that had lighter bands of a decidedly reddish colour, resulting in intense black stripes alternating with a rusty red background. This latter cat produced kittens with extreme reddish tones, indicating the extreme reddish tone was hereditary.
Two pregnant females of common cats brought into the laboratory produced kittens with a peculiar ashy colour and darker extremities. The colour distribution resembled that of adult Siamese cats, but the kittens went on to develop normal solid colouration. The inheritance of the peculiar ashy colour could not be followed out at the time the kittens were on hand and Whiting could not determine whether it represented the heterozygote for Siamese dilution. His thinking was actually on the correct track because both fever coat and the Siamese pattern are temperature-related.
White and White Spotting
Whiting also studied the inheritance white spotting, which he knew to be independent of other colours. Solid white, W, appeared to be a simple complete dominant over colour, w, and possibly allelomorphic with one or more of the white spotting factors. He noted that solid white was true-breeding in the hands of fanciers.
White-spotting in cats graded all the way from solid-white to self-colour. It was independent of other colour factors and appeared more commonly on the under parts. He noticed that the different amounts of white formed distinct patterns (locket, tuxedo etc), rather than being an increase in random white spots on the body. He termed the degrees of white spotting “restricted,” “moderate” and “considerable.” White spotted cats could carry self-colour, and self-colour cats bred true. It was obvious to Whiting that although extensively pigmented animals appeared among the offspring of cats showing much white there was little tendency for a kitten to show more white than either parent. Whiting considered that the interesting correlation of blue eyes and deafness with white coat was not satisfactorily explained. He suggested a quadruple allelomorphic series: W (solid-white); wm (much spotted); wl (little spotted); and w (non-spotted/self) in that order of dominance.
Whiting also noticed an interesting but unexplained relationship between yellow-spotting (tortoiseshell) and white-spotting. "Self" tortoiseshells (those without white) had yellow and black hairs intermixed. Tortoiseshells with restricted white-spotting tended to have yellow separated into patches, while further extension of white separated yellow and non-yellow areas still more. Separation of yellow into patches did not correlate with the amount of yellow, but correlated with the amount of white.
Whiting's ideas on white proved to be true. Work by David, O'Brien, Meynotti-Raymond et al. have shown that there is one locus, one allelic series, where white spotting takes the intermediate position. Below is the core of Whiting's idea of one series:
“The failure of anything higher than ‘restricted’ spotting to occur among the offspring of restricted x self, although cats with ‘considerable’ spotting may carry self, indicates that there may be allelomorphic factors determining different degrees of spotting. In any case it appears that self is recessive to spotting and that color is recessive to solid-white. The principle is suggested that there is a quadruple allelomorphic series:– W, solid white; wm, much spotted; wl, little spotted; and w, self, with dominance in the degree of decreasing pigmentation.”
We now know that the amount of white spotting is not encoded in that locus, and there is no genetic difference between “much” white and “little” white. However, for quite a long time a different theory, with two different loci for epistatic white and white spotting was universally accepted. Robinson speaks of that theory as established fact. Where in early genetics did this theory appear? There was one study in Schwangart's book, a reference to an old agricultural article in German. But there were no other studies or experiments. So what made the two loci theory for white theory popular? Possibly it was Ruth C Bamber (Mrs Bisbee) in her paper "Correlation between white coat colour, blue eyes and deafness in cats. Journal of Genetics, 1933":
“Whiting, in 1918, recorded a black and white cat with odd eyes, one blue and one yellow, he adds that the hair around the blue eye was white, whilst that around the yellow eye was black. On the strength of this observation he suggested that in white cats ‘the incidence of white spotting in connection with the dominant white factor produces the blue eyes,’ that is, that " a 'white spot' about the eye of a white cat makes the eye blue, while a 'pigment spot' about the eye of a solid white cat makes the eye yellow. It may be also that a 'white spot' in the ear of a white cat makes it deaf." According to this suggestion every blue-eyed white cat should carry white spotting. Now solid white is probably the extreme condition of white spotting, the end member of a series of multiple allelomorphs leading from self-colour, through different (degrees of white-spotting, to solid white (Castle, 1916; Wright, 1918; Whiting, 1919; Kuhn & Kroning, 1928). If this be fact, then one animal which came under my own observation would go far towards making Whiting's [one locus] hypothesis untenable. This animal was a white, blue-eyed, completely deaf male, produced from the cross Self-black female × White male. As self-black is recessive to any degree of white spotting (Whiting, 1919; Kuhn & Krohning, 1928), the white son could not have received white spotting from his mother. Neither could he have received it from his father if self-white is allelomorphic to white spotting, he almost certainly did not carry white spotting, yet his eyes were pure blue and he was completely deaf. As the relationship of white to white spotting is not yet fully established, however, the above case may not be as conclusive evidence against Whiting's hypothesis as it at present appears to be.”
Eye Colours
Dominance of eye colour seemed irregular. Whiting noted that blue eyes in pigmented cats were rare, except in the case of the Siamese. His working hypothesis was that white-spotting in connection with the dominant white factor produced the blue eye, or in other words a 'white spot' about the eye of a white cat made the eye blue, while a 'pigmented spot' about the eye of a solid white cat makes the eye yellow. A 'white spot' in the ear of a white cat might make it deaf. This explained why it was difficult to get blue-eyed white cats with normal hearing: it was difficult to localize the 'white spot' upon the eye and to keep it away from the ear. Whiting’s theory was correct since melanin, which produces coat pigment, is also important for the functioning of the inner ear.
A SELECTION OF PAPERS CITING WHITING’S CAT STUDIES
Whiting’s work formed the basis of many other studies into cat colour genetics and he is still quoted today. His hypotheses on tortoiseshell were only partly correct due to incomplete knowledge of the sex chromosomes at the time: the fact that yellow was the sex-linked colour, not black, and that the Y chromosome did not carry any colour genes. His observations of white distribution and deafness were correct. References to his works are in chronological order.
Tricolour Inheritance.III. Tortoiseshell Cats - Heman L. Ibsen (1916)
C. C. Little, Colour inheritance in cats, with special reference to the colours black, yellow and tortoiseshell, Journal of Genetics, 8, 4, (279-290), (1919).
Kuhn, A. und Kroning, F. (1928). "Uber die Vererbung der Weiszcheckung bei der Hauskatze." Zeits. Züchtungskunde, Göttingen,3, Heft 9, pp. 448–54.
Ruth C. Bamber (Mrs Bisbee) and E. Catherine Herdman. Dominant Black in Cats and its Bearing on the Question of the Tortoiseshell Males--A Criticism. By 1927
Ruth C. Bamber, E. Catherine Herdman, A report on the progeny of a tortoiseshell male cat, together with a discussion of his gametic constitution, Journal of Genetics, 26, 1, (115-128), (1932).
Ruth C. Bamber, Correlation between white coat colour, blue eyes and deafness in cats, Journal of Genetics, 27, 3, (407-413), (1933).
A. G. Searle, Gene frequencies in London's cats, Journal of Genetics, (214-220), (1949).
Roy Robinson, "Genetics For Cat Breeders," (1971)
Roy Robinson, Gene Assortment and Preferential Mating in the Breeding of German Fancy Cats, Heredity, 25, 2, (207-216), (1970).
Silvia Heid, Rainer Hartmann, Rainer Klinke, A model for prelingual deafness, the congenitally deaf white cat – population statistics and degenerative changes, Hearing Research, 115, 1-2, (101-112), (1998).
M. P. Cooper, N. Fretwell, S. J. Bailey and L. A. Lyons, White spotting in the domestic cat (Felis catus) maps near KIT on feline chromosome B1
2005 International Society for Animal Genetics, Animal Genetics, 37, 163–165.
Cooper, M. M. et al. “White spotting in the domestic cat (Felis catus) maps near KIT on feline chromosome B1.” Animal Genetics 37 (2006): 163 - 165.
Chris Kaelin, Greg Barsh, Tabby pattern genetics – a whole new breed of cat, Pigment Cell & Melanoma Research, 23, 4, (514-516), (2010).
Christopher B. Kaelin, Kelly A. McGowan, Gregory S. Barsh, Developmental genetics of color pattern establishment in cats, Nature Communications, 12, 1, (2021).
Other papers referencing Whiting (no quotations available):
RATS
EUGENICS
INSECTS