Clinical Endocrinology ( 1988), 29,485-494

IN-VIVO AND IN-VITRO ENDOCRINE INVESTIGATION OF PURE GONADAL DYSGENESIS

S . C. WILSON, R. E. OAKEY A N D J . S . SCOTT

Division of Steroid Endocrinology, Department of Chemical Pathology and Department of Obstetrics and Gynaecology. University of Leeds. England

( Receiued 26 Februury 1988; rerurned for revision 6 Muy 1988:finally reiised I June 1988; ucrepred I7 June 1988)

S U M M A R Y

Diagnosis of XY pure gonadal dysgenesis was established in a patient of female phenotype, with female internal genitalia, but with a chromosomal constitution of 46 XY. Streak gonads had undergone neoplastic transformation-gonado- blastoma and dysgerminoma. Before operation the concentrations of gonado- trophins in plasma were high and of oestradiol was low. Administration of oestradiol benzoate initially suppressed and then stimulated an increase in the plasma concentration of LH. These changes were not accompanied by changes in blood levels of endogenous sex steroids. A single injection of hCG failed to stimulate steroid secretion. The activities in uitro of steroid-metabolizing enzymes in the dysgenetic gonadal tissue more closely resembled those of ovarian tissue from a premenopausal and from a postmenopausal woman than those in testes from two androgen-insensitive patients. However, aromatase activity was higher in the dysgenetic gonads than in the pre or post-menopausal ovaries. Examination of enzymes in genital skin fibroblasts demonstrated normal activities of 3a/P-b-hydroxysteroid dehydrogenase and 17P-hydroxys- teroid dehydrogenase (oxidative and reductive directions). However, 5a- reductase activity was low in minces and fibroblasts of genital skin from the patient. Androgen binding was within the range for male controls.

Swyer (1955) described two tall, outwardly normal female patients with female internal genitalia but of male chromosomal constitution. Further reports of Swyer’s syndrome, or XY pure gonadal dysgenesis, have mostly been concerned with! the high incidence of neoplastic transformation of the streak gonads (Teter & Boczkowski, 1967; Andrews, 197 1 ; Schellhas, 1974).

The few endocrine reports describe low concentrations of oestrogen in peripheral and gonadal venous blood (Phansey et al., 1980) with androgens in the range for normal females (Moreira-Filho er al., 1979). Gonadotrophin secretion is high (Blanchet et al., 1974; Moreira-Filho er al., 1979) and there is little or no steroid secretion in response to injections of hCG (Bardin et al., 1969; Moreira-Filho et al., 1979).

Correspondence: Dr S. C. Wilson, Division of Steroid Endocrinology, Department of Chemical Pathology, University of Leeds. 26-28 Hyde Terrace. Leeds LS2 9LN, England.

48 5

486 S. C. Wilson et al.

Information concerning the ability of dysgenetic gonads to synthesize steroids in uitro is sparse and the few studies have been of tissue from virilized patients. Griffiths et al., (1966) demonstrated in uitro the capacity of a gonadal tumour from such a patient to produce testosterone and oestradiol from progesterone. Furthermore, Bardin et al. (1 969) described the activities of enzymes in the gonads of a virilized patient with raised blood levels of testosterone and androstenedione. However, most patients with XY pure gonadal dysgenesis are not virilized.

It was considered pertinent to investigate the activities of enzymes in the gonads of a patient who showed no virilization yet had developed gonadoblastoma and dysgermi- noma in both gonads. Availability of genital skin also permitted an assessment of the characteristics of the androgen receptors and of the activities of enzymes involved in the peripheral metabolism of androgens in this condition.

MATERIALS AND METHODS

Patient

The patient, of average height, slim build, with no obvious physical anomalies, presented at 18 years of age with primary amenorrhoea. She had experienced some breast development 2-3 years previously but had not received hormonal treatment before admission. Chromosomal constitution of blood leucocytes, ascertained on three separate occasions was 46 XY. A 16-year-old sister had normal menarche at the age of 13 years. On examination, the patient had moderately developed breasts with some glandular

tissue but small nipples. Axillary and pubic hair resembled those of a normal adult female as did the external genitalia. The vagina was of normal length but the uterus was small. Laparoscopy confirmed the small hypoplastic uterus (3.2 cm length) and showed normal- looking Fallopian tubes. Pelvic X-ray showed calcification in the region of the gonads. Biopsies of each gonad revealed stroma of an indeterminate type with the presence of Call-Exner bodies, indicative of gonadoblastoma. A biopsy of genital skin (labium majorum), taken at this time, was retained for measurement of enzymes and, after culture, for studies of enzymes and androgen receptors in fibroblasts (approved by the local Ethical Committee).

Histology of gonads

In view of the pathological findings, laparotomy was performed 2 months later for removal of the gonads. The left gonad measured 23 x 16 x 12 mm and histologically was composed of ovarian stroma resembling interstitial (Leydig) cells with tubules of variable sizes and nests of malignant germ cells. The right gonad (30 x 18 x 10 mm) consisted of stroma with interstitial (Leydig) cells or lutein cells of fibrous appearance and also contained gonadoblastoma with abundant calcific concretions. There were also several tubules with atypical germ cells and peripheral Sertoli-like sex-cord stromal cells. There was evidence of gonadoblastoma and dysgerminoma in both gonads. Half of each gonad (longitudinal section) was frozen immediately after removal and retained for enzyme studies.

r

Pure gonadal dysgenesis 487

In-uiuo endocrine studies

Tests, carried out 2 months before gonadectomy, investigated the responses to injections (i.m.) of 1 mg oestradiol benzoate on days 0, I , 2 and 3 (oestrogen provocation test) and to a single injection (i.m.) of 5000 IU hCG on day 5 (hCG stimulation test). A blood sample was taken immediately before the first oestrogen injection (day 0) and thereafter on days 1, 2, 3, 4, 5 and 7. For purposes of comparison, data are presented from a 46 XY chromosomal male patient (22 years) with incomplete androgen insensitivity syndrome similarly given injections of I mg oestradiol benzoate (i.m., days 0, 1, 2, 3) and from a female patient (28 years) with Mullerian regression syndrome given a single i.m. injection of 5000 IU hCG.

In-vitro studies

Enzyme activities of gonads (minces) and skin (minces and cultured fibroblasts) and androgen receptors of skin fibroblasts were measured.

Enzymes in gonads

The capsule was removed and the gonad finely chopped. Portions (100 mg) were incubated with ['HI-steroid substrate (8 pmol; Amersham International, Bucks., England) and cofactors (Sigma, Poole, Dorset, England) NADP+ (100 nmol). NAD +

( 1 pmol) or NADPH (50 nmol) in Krebs-Ringer phosphate buffer, pH 7.4. The total incubation volume was 1 ml. Following incubation for 30, 60 or 120 min, at 37°C in a shaking water bath, the reactions were stopped by rapid cooling on ice. Appropriate carrier steroids and ['4C]-labelled steroids were added and these, together with the [3H]- steroids from the incubation, were extracted with toluene (5 ml). The steroids were partitioned into phenolic and neutral components by the addition of 2 M NaOH ( 1 ml). The toluene fraction was removed and the solvent evaporated. The phenolic fraction was neutralized by the addition of I 1 M HCI (0.2 mi) and the steroids extracted twice into diethyl ether (3 ml). The combined ether extracts were evaporated. Steroids from the phenolic and neutral fractions were separately reconstituted in chloroform (40 p l ) and chromatographed on plastic-backed, silica gel-coated thin layer chromatography plates in a solvent system of chloroform-methanol (97.8 : 2.2). Zones corresponding to appropriate reference steroids were cut out and assayed for tritium and I4C. Fractions containing (i) progesterone and androstenedione, and (ii) testosterone, 17a-hydroxypro- gesterone, dehydroepiandrosterone and pregnenolone were subjected to further chromatography on a system of toluene-ethyl acetate (9 : 1) to improve the separation of these steroids. For purposes of comparison, measurements were made of enzyme activities in macroscopically normal gonads from a premenopausal (42 years) and a postmenopausal (60 years) woman who had undergone salpingo-oophorectomy sub- sequent to diagnosis of endometriosis and endometrial cancer respectively and in testes from two patients with incomplete (15 years) or complete (18 years) androgen insensitivity syndrome. Identity of products from incubations was confirmed using testicular tissue. A constant ratio of [3H] : ["C] was maintained in pooled fractions subjected to further chromatography on a system of toluene-methanol, 7 : 3 and then to derivative formation by oxidation, reduction or acetylation procedures.

488 S. C. Wilson et al.

Enzymes in skin Activities of enzymes involved in the metabolism of androgens were determined in

genital skin minces and in fibroblasts cultured from genital skin as described previously (Wilson et al., 1988). For purposes of comparison, activities of enzymes in minces of genital skin (labium majorum) from a patient with incomplete masculinization due to testicular 17j5hydroxysteroid dehydrogenase deficiency (1 7j-HSD deficiency, 15 years) and from five normally differentiated prepubertal males (foreskin) were measured. Genital skin fibroblast cell-lines for comparison were derived from patients with hypogonadotrophic hypogonadism (labium majorum, 22 years), testicular 17fl-HSD deficiency (labium majorum, I3 years), incomplete androgen insensitivity syndrome (labium majorum, 16 years) and two normally differentiated prepubertal males (foreskin).

Androgen receptors

were measured using the method described by Hodgins (1982). Maximal androgen binding capacities of androgen receptors in genital skin fibroblasts

RESULTS In-uivo endocrine studies

Baseline concentrations ofgonadotrophins andsex steroids The concentrations of FSH (78 IU/I) and LH (30 IU/I) in a blood sample taken at an initial visit were markedly raised in comparison with those of normal adult males (FSH, 3-10 IU/l; LH, 10-25 IU/I) and females (FSH, c 8 IU/l; LH, < 10 IU/l). The ratio of FSH to LH (2.5) was also raised. The concentration of oestradiol (45 pmol/l) was well below the normal adult female range (200-2000 pmol/l), whilst androstenedione (6.5 nmol/l), testosterone (1 -3 nmol/l) and 5a- dihydrotestosterone (0.6 nmol/l) were within the range for normal females.

Oestrogen provocation test Administration of oestradiol benzoate ( 1 mg) on each of four successive days caused an

initial decline in LH during the first 2 days, followed by a rise to pre-treatment level by day 4 in both the patient with pure gonadal dysgenesis and in a postpubertal patient with incomplete androgen insensitivity syndrome (AIS; Fig. I ) . In the patient with pure gonadal dysgenesis the concentration of LH rose further to 114 IU/l on day 5, this value being substantially greater than the pre-treatment concentration of 30 IU/I. No sample was taken on day 5 from the patient with incomplete AIS. The concentration of FSH, which was considerably higher in the patient with pure gonadal dysgenesis than in the patient with incomplete AIS, declined during the first 2 days of oestrogen injections and remained low during the treatment period.

There were marked differences in the patterns of steroid secretion during oestrogen treatment of the two patients. In the patient with incomplete AIS, the decline in LH was accompanied by a steep fall in plasma testosterone concentrations (Fig. 1). No analogous changes were found in the patient with gonadal dysgenesis during the 5 day test.

hCG stimulation test In the patient with pure gonadal dysgenesis, a single injection with hCG (5000 IU)

failed to stimulate any increase, at 48 h, in the plasma concentrations of androstenedione (5.0 to 3.4 nmol/l), testosterone (1.4 to 1.0 nmol/l) or progesterone (3.0 to 2.0 nmol/l). This contrasted with increases in each of these steroids in a similarly treated control patient

Pure gonadal dysgenesis

80

60

40

20

0-

489

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-

-

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38

30

22

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-

-

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Time (days)

Fig. 1. Concentrations in plasma of gonadotrophins (LH, O--O; FSH, 0- - -0) and steroids (testosterone, .- . - 4; progesterone, 0 . . ' 0 ; androstenedione, A---A) in subjects with (left) XY pure gonadal dysgenesis (I8 years) and (right) incomplete androgen insensitivity syndrome (22 years) both given daily injection of oestradiol benzoate (EzB, 1 mg i.m.) on days 0 to 3.

with Mullerian regression syndrome (androstenedione, 1 1-0 to 15.9 nmol/l; testosterone, 2.5 to 2.9 nmol/l; progesterone, 22.0 to 44.0 nmol/l).

In-vitro studies

Enzymes in gonads

Activities of enzymes involved in catalysing steroidogenesis (Fig. 2) in the dysgenetic gonads and tumour tissue more closely resembled those in ovaries taken from premenopausal (42 years) and postmenopausal (60 years) women than those in testes from peri/postpubertal patients (1 5 and 18 years) with AIS. An exception was aromatase activity (Fig. 3) which matched the higher levels found in testicular than in ovarian tissue.

490 S. C. Wilson et a/.

The quantitative dissimilarity in enzyme activity between the different types of gonadal tissue is illustrated by the extent to which the various substrates were metabolized. For example, there was significant I7a-hydroxylation of pregnenolone by all tissues (Fig. 2a). However, the major metabolite of this substrate recovered from incubations with the dysgenetic gonad tissue and the postmenopausal ovary was 17a-hydroxypregnenolone, whereas testicular tissue and the premenopausal ovary converted this further to dehydroepiandrosterone (Fig. 2a). In all other incubations, conversion of substrate by the premenopausal ovary was only slightly higher than that of the postmenopausal ovary. Conversion of 17a-hydroxyprogesterone (Fig. 2b) to androstenedione and thence to testosterone was low in the dysgenetic gonads and in ovaries as compared with testicular tissue. Similarly, the reduction by 17P-HSD of dehydroepiandrosterone to androstene- diol (Fig. 2c) and of androstenedione to testosterone (Fig. 2e) was much lower in the ovaries and dysgenetic gonads than in testes, as was oxidation by 17B-HSD of testosterone to androstenedione in the presence of NADP+ (Fig. 20. Conversion of testosterone to androstenedione, in the presence of NADPH, was negligible in the ovaries and dysgenetic gonads but, in testicular tissue, was of similar proportion to that obtained during incubation with NADP+ as cofactor.

Differences were observed in enzyme activities between the left and right dysgenetic gonads. This was particularly evident with regard to reduction by 17P-HSD of substrate androstenedione to testosterone (Fig. 2e) and of dehydroepiandrosterone to androstene- diol and testosterone in the presence of NADPH (Fig. 2c); activity of this enzyme in the right gonad tended to be higher than the left and higher than activity in the right ovary of either pre or post-menopausal women (Fig. 2c, e).

Formation of oestrogens (Fig. 3) from the Ct9 steroids (dehydroepiandrosterone, androstenedione, testosterone) was consistently higher in dysgenetic gonadal tissue than in ovarian tissue from either pre or post-menopausal women and, in contrast to activities of other enzymes, more closely resembled those of testicular tissue.

Enzymes in skin Conversion of the substrate testosterone by 5a-reductase was lower in genital skin

minces of the patient with pure gonadal dysgenesis than in skin taken from male controls (Table 1). Similarly, activity of 5a-reductase in genital skin fibroblasts from our patient was lower than in control cell-lines when either testosterone or androstenedione were used as substrates. In contrast, activities of 3a/D-HSD, 17j-HSD (reductive direction) and 178- HSD (oxidative direction) in genital skin fibroblasts were within the range of controls (Table 1).

Androgen receptors Maximal binding of [3H]-dihydrotestosterone to androgen receptors in genital skin

fibroblasts of the patient with pure gonadal dysgenesis (40.9 fmol ['HI-dihydrotestoster- one bound/mg protein/h) was similar to that in cell-lines established from three patients with incomplete masculinization (hypogonadotrophic hypogonadism 2 1 a 0 fmol; testicu- lar 17P-HSD deficiency 26.1 fmol; incomplete AIS 27.7 fmol) and from one normally masculinized prepubertal patient (41 -5 fmol).

I

DISCUSSION

The diagnosis of 46 XY pure gonadal dysgenesis in our patient was established at

Pure gonadal dysgenesis 49 1

P (01 Pregnenoione, NADPH F

tfl C

II HA Androsfenediol ..I J A T

1 lel Androstenedione, NADPH

: I L Jdl T

(bl 17.*-CHprogesterone, NAOPH

( I ) Testosterone, NADP'

I n l

Fig. 2. In-vitro metabolism of 8 pmol C21 and Clp steroids by left and right gonads and associated tumour tissue of a patient with XY pure gonadal dysgenesis (dys. gonads; 18 years), right ovaries of postmenopausal (60 years) and premenopausal (42 years) women and testes from patients with complete (18 years, left gonad) or incomplete (15 years, right gonad) androgen-insensitivity syndrome. Results are expressed as yietds of ['HI major metabolites in pmo1/100 mg tissue. Cofactors were NADPH (50 nmol), NADP+ (100 nmol) or NAD' ( I pmol). Periods of incubation: (a) and (b) 75 min all tissues; (c) and (d) 60 min dysgenetic gonads and ovaries. 20 min testes; (e) and (f) I20 min dysgenetic gonads and ovaries, 30 rnin testes.

492 S. C. Wilson et al. DHA, DHA, Androstenedione, Testosterone, Testosterone,

NADPH NADP' ,NAD' N A D P H NADP' NADPH

dM m Fig. 3. Conversion of C19 steroid substrates to oestrogen by dysgenetic gonads, ovaries and testes. The period of incubation of tissue with testosterone in the presence of NADPH was 120 min dysgenetic gonads and ovaries. 30 min testes. Other incubations and key as in Fig. 2. *, Not determined.

laparotomy. Whilst the vagina and Fallopian tubes were of normal size and appearance, the uterus was small and hypoplastic, suggestive of inadequate oestrogen stimulation, though there were no features of Turner's syndrome. The plasma concentration of FSH was substantially greater than that of LH, as observed previously (Boyar et a/., 1973; Kim

Table I . In-vitro metabolism ofCl9 steroids by genital skin of a patient with XY pure gonadal dysgenesis and male controls

Genital skin minces (7.5 pmol substrate)* 5a-reductase activity (pmol/50 mg skin/30 min)

T+ DHT, androstanediol, androstanedione

Genitul skinjbroblrrsts (4-5 pmol substrate)? Sa-reductase activity (pmolfmg protein/30 rnin) T-DHT. androstanediol. androstanedione A-androstanedione

Pure gonadal Controls d y sgenesis

0.34 1.36fO-3 (SEM)

0.15 5.92 f 2.8 0.45 5.76 f 2.3

I7p-hydroxysteroid dehydrogenase reductive activity (pmol/mg protein/h) A+T 0.10 ' 0.29f0.1

17~-hydroxysteroid dehydrogenase oxidative activity (pmol/rng proteinlh) T-rA 0.97 0.53 f 0.3

2.22f 1.5 DHT-androstanedione 2.10

3a/p-hydroxysteroid dehydrogenase activity (pmol/mg protein/h) 0.90 f 0.2 DHT-androstancdiol 1.51

T, testosterone; DHT, Sa-dihydrotestosterone; A. androstenedione. For genital skin fibroblasts, figures represent the mean of three assays performed between the 6th and 12th subculture.

Six controls. t Five controls.

Pure gonadal dysgenesis 493

et al., 1974; Van Look et al., 1977), suggestive of a failure of FSH suppression by the inadequate oestrogen noted or inhibin (Baker et al., 1976).

Despite the bilateral gonadoblastoma and dysgerminoma, plasma concentrations of androgens were within the range for normal adult females and there was no evidence of abnormal virilization. Breast development was noted, a feature not commonly observed in XY pure gonadal dysgenesis. In XY chromosomal individuals of female phenotype this is usually attributed to excessively high secretion of oestrogen and/or reduced suppressive action of androgen during embryonic development. However, neither of these conditions apply to our patient in whom oestrogen secretion was very low and binding of androgen to receptors in genital skin fibroblasts was apparently normal.

The effectiveness of exogenous oestrogen initially to suppress and later to evoke a release of LH is consistent with previous reports of a female-type pattern of response (Leydendecker et al., 1971; Van Look et al., 1977). The time course of the response was similar to that of normal women treated with oestrogen during the early to mid-follicular phaseofthecycle(Yen&Tsai, 1972;Van Look etal., 1977). Althoughduring thefirst48 h of oestrogen treatment, FSH concentrations declined in a manner similar to those of LH, stimulation of FSH secretion was not evident, substantiating the findings of Van Look et al. (1977).

During the course of oestrogen injections, the concentrations of other steroids in the blood of the patient with pure gonadal dysgenesis did not decline in response to the fall in circulating LH. This contrasts with the close temporal relationship between LH and testosterone in patients with the syndrome of androgen insensitivity in this and other studies and in oestrogen-treated men (Van Look et al., 1977).

In our patient with pure gonadal dysgenesis, dissociation between secretion of sex steroids and LH was consistent with the failure of hCG to stimulate steroidogenesis. The circulating androgens present could have originated from adrenal and from peripheral conversions rather than from gonadal tissue, in which case their production would not be modified by changes in gonadotrophin secretion. However, others (Weiland et al., 1968; Phansey et al., 1980) have demonstrated androgen production by dysgenetic gonads after comparison of androgen levels in gonadal and peripheral vein samples.

Both dysgenetic gonads showed, in vitro, the ability to convert C?, steroid precursors to androgens and C19 steroid precursors to oestrogens. Bardin et al., (1969) described testosterone production in vitro by gonadal tissue of a virilized patient with XY pure gonadal dysgenesis and Leydig cell hyperplasia as being intermediate between that of ovarian stroma from a postmenopausal woman and a testicular Leydig cell preparation. In contrast, in incubations of tissue from our non-virilized patient, production of testosterone was much closer to that of ovarian tissue, and considerqbly lower than that of testes. It was noticeable that the right gonad and tumour produced substantially more testosterone than the left during in-vitro incubations although this could not be attributed to any gross difference in extent of neoplastic transformation of the gonads. The capacity of the dysgenetic gonads to aromatize androgens to oestrogen to a greater extent than that of ovarian tissue may be attributed to the presence of gonadoblastoma and dysgermi- noma. In view of the potential of the gonadal tissue for androgen and oestrogen biosynthesis in vitro, the findings in vivo may imply a deficiency in gonadotrophin receptors or in cholesterol utilization by the gonadal tissue.

Activities of the enzymes 3aIB-HSD and 17P-HSD in genital skin fibroblasts were within the range of male controls. In contrast, the activity of Sa-reductase in genital skin

494 S. C. Wilson et al.

fibroblasts and skin minces was lower than that of thecontrols. The wide range ofactivity of Sa-reductase within the controls rendered the interpretation of data from a single patient difficult and the significance, if any, of the low activity of 5a-reductase awaits similar investigations of other patients with pure gonadal dysgenesis.

ACKNOWLEDGEMENTS

We are grateful to the staff of the Leeds Supraregional Assay Services Steroid Centre for the steroid assays, the Department of Chemical Pathology, Leeds General Infirmary, for the gonadotrophin estimations and the Department of Pathology for histological assessment of gonadal tissue.

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KEOGH, E.J., LEE, V.W.K. & RENNIE, G.C. (1976) Testicular control of follicle-stimulating hormone secretion. Recent Progress in Hormone Research, 32,429-476.

BARDIN, C.W., ROSEN, S., LEMAIRE. W.J.,TJIO. J.H.. GALLUP, J. . MARSHALL, J. & SAVARD, K. (1969) In uivo and in vitro studies of androgen metabolism in a patient with pure gonadal dysgenesis and Leydig cell hyperplasia. Journal of Clinical Endocrinology and Metabolism. 29, 1429-1437.

BLANCHET, P., DALOZE, P., LESAGE, R., PAPAS, S. & CAMPENHOUT. J. (1974) XY gonadal dysgenesis with gonadoblastoma discovered after kidney transplantation. American Journal of Obstetrics and Gynecology,

BOYAR, R.M., FINKELSTEIN, J.W.. ROFFWARG. H., KAPEN, S., WEITZMAN, E.D. & HELLMAN. L. (1973) Twenty- four-hour luteinizing hormone and follicle-stimulating hormone secretory patterns in gonadal dysgenesis. Journal of Clinical Endocrinology and Metabolism, 37. 521 -525.

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HODGINS, M.B. (1982) Binding of androgens in Sol-reductase-deficient human genital skin fibroblasts: inhibition by progesterone and its metabolites. Journal of Endocrinology. 94, 415-427.

KIM, M.H., HOSSEINIAN, A.H.. SACRIS. M.O., DUPON. C. & CLEARY, R.E. (1974) Hormonal profile in patients with gonadal dysgenesis. American Journal of Obstetrics and Gynecology, 118.955-960.

LEYDENDECKER, G.. WARDLAW, S.. LEFFEK. B. & NOCKE. W. (1971) Studies on the function of the hypothalamic sexual centre in the human: presence of a cyclic centre in a genetic male. Acta Endocrinologica. Suppl. 155, Abstract 36.

MOREIRA-FILHO, C.A.. TOLEDO, S.P.A.. BAGNOLLI. V.R., FROTA-PESOA. 0.. BISI, H. & WUNTAL, A. (1979) H-Y antigen in Swyer Syndrome and the genetics of XY gonadal dysgenesis. Human Genetics, 53.51-56.

PHANSEY, S.A., SATT€RFIELD, R., JORGENSON, R.. SALINAS, C.F., YODER, F.E.. MATHUR, R.S. & WILLIAMSON, H.O. (1980) XY gonadal dysgenesis in three siblings. American Journal of Obstetrics and Gynecology, 138,

SCHELLHAS, H.F. (1974) Malignant potential of the dysgenetic gonad. Part I. Obstetrics and Gynecology, 44,

SWER. G.I.M. (1955) Male pseudohermaphroditism: a hitherto undescribed form. British Medical Journal, 2.

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