Ruth Sanger

Early fusion of two human embryos

An infant chimaera with an XX and an XY cell line is described. She had a macroscopically and histologically normal ovary on the right and an ovotestis on the left. Biopsies from the gonads revealed 1–15% of XY cells as judged by fluorescent Y body findings of uncultured cells as well as by karyotypes of mitoses from long term cultures. Ovarian and testicular structures had similar frequencies of the two cell lines. There was no evidence of in vitro selection of cells during tissue culture.

Data for X-mapping calculations, Israeli families tested for Xg, g-6-pd and for colour vision

The results are recorded of tests for the X‐linked red cell antigen Xga on families with glucose‐6‐phosphate dehydrogenase deficient members. The families live in Israel and belong to Kurdish, Iraqi, Yemenite, Sefardic and Ashkenazy Communities.

The linkage relations of the loci for benign (Becker type) X‐borne muscular dystrophy, colour blindness and the Xg blood groups

A relatively benign form of X-linked muscular dystrophy was first recognized by Becker (Becker, 1955, 1957, 1962; Becker & Kiener, 1955). In this type of muscular dystrophy, muscle weakness first becomes evident in the teens or early twenties and affected individuals usually become confined to a wheelchair only after about 20 years and the majority survive at least into middle age. Weakness begins in the pelvic girdle musculature, only later affects the upper limbs and in most cases there is pseudohypertrophy of the calf muscles. There is no clinical or biochemical feature specific for this type of muscular dystrophy; the diagnosis is made when several males affected with a limb-girdle form of muscular dystrophy occur in the same family and the pattern of inheritance is consistent with that of an X-linked recessive trait. The relationship of this to other forms of muscular dystrophy has been discussed in detail elsewhere (Emery & Walton, 1967). In a recent report Blyth and her colleagues (1965) in analysing two families with Becker-type muscular dystrophy were unable to draw any conclusions regarding the possibility of measurable linkage with Xg but the results suggested that more families should be tested: these two families are added to the analysis of three further families about to be described. A family originally reported by Philip, Walton & Smith (1956) in which deutan colour blindness and muscular dystrophy were segregating was restudied and the pedigree extended. Though originally reported as the severe Duchenne type of muscular dystrophy it is clear that the disease in this family would now be classified as Becker-type muscular dystrophy (Emery, 1968). The results of linkage studies in this family are reported in the present communication.

Linkage relations of X‐borne ichthyosis to the Xg blood groups and to other markers of the X in Israelis

A series of families in the counties around Oxford (Kerr, Wells & Sanger, 1964) gave the first indication that there was reasonably close linkage between the Xg blood groups and the X-borne type of ichthyosis. This stimulated the investigation in Israel of which the present paper gives the full account (it includes the data of an interim report by Adam et al. 1966). The Oxford findings also stimulated a survey based on London (Wells et al. 1966). These three publications established beyond any doubt that the locus for Xg is close to that for ichthyosis. The survey in Israel included tests for glucose-6-phosphate dehydrogenase (g-6-pd) aa well as for colour vision.

X‐linked ichthyosis: linkage relationship with the Xg blood groups and other studies in a large Dutch kindred

Three propositi with probable X-linked ichthyosis were found from the files of the Dermatology Department of the Binnengasthuis (University Hospital, Amsterdam). These propositi and some of their relatives were seen at the Dermatology Clinic and they, together with the files of the Civil Registration Office, provided complete pedigrees. Preliminary tests showed the family of one of the propositi not to be informative with regard to the main purpose of the investigation : all those tested were Xg (a + ) and the mother, who is dead, had come from Germany. The other two propositi were both thought to have had an Italian great-great-great-grandfather and subsequently, as a result of the investigation, were shown to belong to one large kindred.

Glucose-6-phosphate dehydrogenase, colour vision and Xg blood groups in Greece: linkage and population data

1. The same recombination frequency (26 %) between the loci for G‐6‐PD and Xg was found in Greek populations as had been found in Israelis. Prof. Siniscalcos data from Sardinia do not agree with this frequency.

ANOMALOUS Xg INHERITANCE WITH A PROBABLE EXPLANATION

Abstract The peripheral blood cells of the mother of three children presented a mosaic karyotype 45,X/46,XX, the two cell lines being in the approximate proportion of 1 to 2. The mother and her husband were phenotypically Xg(a—), but two of the three children were Xg(a+). It was assumed, because of her fertility, that her gonads were, at least in part, 46,XX; and, because of the aberrant Xg inheritance, that her constitutional genotype was Xg a Xg but that her red cells were derived from a predominantly 45,X line. The latter presumption was supported when the karyotype of her marrow showed about 90% of the cells to be 45,X.