Restriction of color in the rat with associated sterility in the male and heterochromia in both sexes

Abstract

The effects of a new dominant gene in the rat are described. This gene, restricted (H' '), causes a marked restriction of the colored areas of the body i n the hooded, irish and self color patterns. Males with this restricted color pattern (Re) exhibit testicular tubular dysgenesis with consequent sterility, and a slightly reduced growth rate. The histological structure of the testis is described. Various experimental studies with the Re males are presented. These studies indicate that the cause of the sterility is a relative insensitivity of the germinal epithelium to pituitary follice-stimulating hormone. There is a high incidence of heterochromia i n Re rats with cream coat color and ruby eye.

Pituitary and testicular function in the restricted (Hre) rat

“…Figure 3 shows a detailed time-course of testicular growth in the Hre rat, compared with control littermates. There were two alterations in the pattern of testicular growth in the H' " rat, namely the plateau of weight in the adult at approximately 400 mg, as reported by others (Gumbreck et al, 1972), and a previously unstudied delay in onset of the pubertal increase in testicular weight by approximately 10-14 days followed by an apparently normal (i.e., parallel to the control) increase in testicular weight until 50-60 days of age.…”

“…In order to understand the complex interactions between various compartments of the testis, several investigators have employed model systems that have a defined abnormality. The H' " rat, first described by Gumbreck et al (1972), has been utilized as a model of primary seminiferous tubule failure (Russell & Gardner, 1974;Musto et al, 1978;Spitz et al, 1983;Anthony, Danzo & Orgebin-Crist, 1984). The onset of infertility in the Hre rat has been shown to occur in adulthood as the result of a progressive depopulation of the seminiferous epithelium (Musto er a [ .…”

“…While Gumbreck et al (1972) initially showed decreased testicular weight in the H' " rat as early as 9 days of age when compared with littermates, little attention has been paid to the possible significance of prepubertal abnormalities of the hypothalamo-pituitary-testicular axis, to the adult onset of infertility, or to the possible use of the H' " rat as a model system for the study of mechanisms of normal sexual maturation.…”

Testis structure in the sys (symplastic spermatids) mouse

“…Numerous genetic disorders affecting the process of spermatogenesis have been previously documented (Bryson, 1943;Bennett et al, 1971;Hunt and Johnson, 1971;Olds, 1971;Johnson and Hunt, 1971;Gumbreck et al, 1972;Russell and Gardner, 1973;Handel, 1987). These have proven of great interest a s they reveal some of the more vulnerable phases of spermatogenesis and, 13 1991 WILEY-LISS, INC at the same time, allow one to speculate on the genetic control of specific events in spermatogenesis.…”

Agonistic behavior between wild and genetically sterile male Norway rats (rattus norvegicus)

“…Stanley and Gumbreck (1964) described a strain of genetically sterile male Norway rats that was larger and more vigorous than wild males. Male sterility in these rats is caused by a pleiotropic expression of a single dominant autosomal gene which also restricts the coat color pattern in carriers (both male and female) (Gumbreck et al, 1971(Gumbreck et al, , 1972. Carrier rats have a white spot on the forehead and variable amounts of white on the legs and venter.…”