Consequences of the ESPE/LWPES guidelines for diagnosis and treatment of disorders of sex development

Ambiguous genitalia of the newborn is the paradigm of a disorder of sex development that demands a multidisciplinary team approach to management. The problem is immediately apparent at birth. Abnormalities of the external genitalia sufficient to warrant genetic and endocrine studies occur in one in 4500 births. In recent decades there have been improvements in diagnosis and early management, particularly with respect to congenital adrenal hyperplasia, the commonest cause of ambiguous genitalia of the newborn. However, dissatisfaction with overall management remains. A Clinical Guidelines and Handbook for Parents generated by a partnership of health professionals and support groups is available on the internet. The professional societies representing paediatric endocrinology responded by organizing a consensus meeting on the management of intersex. This resulted in the publication of a Consensus Statement encompassing many aspects of management, extending from birth to adulthood.

Genital Anomalies in Klinefelter’s Syndrome

BACKGROUND/AIMS

Klinefelter's syndrome is characterized by progressive testicular failure causing aspermatogenesis and androgen deficiency. Klinefelter patients classically have complete male sex differentiation, and genital anomalies are generally not recognized as associated features of the syndrome.

METHODS

We reviewed the cases of Klinefelter's syndrome with genitalia abnormalities from the Cambridge Disorders of Sex Development Database, and also reviewed previous case reports of genital anomalies associated with Klinefelter's syndrome and its variants.

RESULTS

We present seven Klinefelter patients with abnormalities of the genitalia, ranging from mild anomalies (chordee) to moderate undervirilisation (bifid scrotum and perineal hypospadias). Two cases were true hermaphrodites with karyotypes 47,XXY and 47,XXY/46,XX respectively. Though androgen insensitivity has been postulated previously as a possible pathogenic mechanism, we demonstrated normal androgen binding in 3 cases in which this was studied. Review of other case reports revealed a range of mild-to-severe abnormalities as well as cases reported as sex reversal, testicular feminization, and true hermaphroditism.

CONCLUSION

Genital anomalies are not commonly observed in Klinefelter's syndrome. However, it is important to acknowledge the association, and recognize Klinefelter's syndrome as one of the causes of abnormal genitalia at birth.

Phenotypic variability in 17beta-hydroxysteroid dehydrogenase-3 deficiency and diagnostic pitfalls

OBJECTIVE

17beta-hydroxysteroid dehydrogenase type 3 isoenzyme (17beta-HSD3) is required to produce testosterone for male sex differentiation. Mutations in the HSD17B3 gene cause 17betaHSD3 deficiency and result in XY sex reversal of varying degree. We report the phenotypes of 14 subjects with 17betaHSD3 deficiency in relation to sex of rearing, androgen production, and HSD17B3 mutations.

DESIGN

Cases were identified through the Cambridge Disorders of Sex Development Database where detailed clinical information was recorded, results of hCG stimulation tests were available, and HSD17B3 mutation was identified.

RESULTS

Fourteen subjects from seven pedigrees (four consanguineous) had the following seven mutations: A56T, N130S, E215D, S232L, C268Y, V205E, and a novel mutation M197K. XY sex reversal was classified as complete in 10 infants at birth. Inguinal masses suggestive of androgen insensitivity syndrome (AIS) occurred in five infants. Contrasexual virilization reminiscent of 5alpha-reductase deficiency occurred in four subjects at puberty. The median (range) testosterone : androstenedione (T/A) ratio after a short hCG stimulation test was 0.32 (0.12-3.4). The S232L mutation identified in three affected family members caused isolated, severe hypospadias in one member who was raised male; virilization occurred despite in vitro studies showing an inactive mutant enzyme. Ratios of T/A in this pedigree were more than 0.8.

CONCLUSION

XY sex reversal is sufficiently variable in 17betaHSD3 deficiency to cause problems in accurate diagnosis, particularly in distinguishing it from AIS. It should be considered in undervirilized male infants with normal Wolffian duct structures, absent Müllerian ducts, and normal adrenal steroid biosynthesis; or when an assigned female subject virilizes at puberty. Elevated hCG-stimulated T/A ratio may occur, and sex of rearing may not be concordant within affected families with the same HSD17B3 mutation. The T/A ratio, mutation analysis and functional analysis of the mutant enzyme taken in isolation, respectively, may not conclusively establish a diagnosis of 17betaHSD3 deficiency in undervirilized male subjects; the reasons for these discrepancies remain unknown.

Heterozygous missense mutations in steroidogenic factor 1 (SF1/Ad4BP, NR5A1) are associated with 46,XY disorders of sex development with normal adrenal function

CONTEXT

Steroidogenic factor 1 (SF1/AdBP4/FTZF1, NR5A1) is a nuclear receptor transcription factor that plays a key role in regulating adrenal and gonadal development, steroidogenesis, and reproduction. Targeted deletion of Nr5a1 (Sf1) in the mouse results in adrenal and gonadal agenesis, XY sex-reversal, and persistent Müllerian structures in males. Consistent with the murine phenotype, human mutations in SF1 were described initially in two 46,XY individuals with female external genitalia, Müllerian structures (uterus), and primary adrenal failure.

OBJECTIVE

Given recent case reports of haploinsufficiency of SF1 affecting testicular function in humans, we aimed to identify SF1 mutations in a cohort of individuals with a phenotypic spectrum of 46,XY gonadal dysgenesis/impaired androgenization (now termed 46,XY disorders of sex development) with normal adrenal function.

METHODS AND PATIENTS

The study included mutational analysis of NR5A1 in 30 individuals with 46,XY disorders of sex development, followed by functional studies of SF1 activity.

RESULTS

Heterozygous missense mutations in NR5A1 were found in four individuals (four of 30, 13%) with this phenotype. These mutations (V15M, M78I, G91S, L437Q) were shown to impair transcriptional activation through abnormal DNA binding (V15M, M78I, G91S), altered subnuclear localization (V15M, M78I), or disruption of the putative ligand-binding pocket (L437Q). Two mutations appeared to be de novo or germline changes. The other two mutations appeared to be inherited in a sex-limited dominant manner because the mother is heterozygous for the change.

CONCLUSIONS

These studies demonstrate that SF1 mutations are more frequent than previously suspected causes of impaired fetal and postnatal testicular function in 46,XY individuals.

Early management and gender assignment in disorders of sexual differentiation

Ambiguous genitalia, sine qua non, defines a congenital endocrinopathy. The problem is immediately apparent at birth and prompts an urgent response in management which requires input from a multi-disciplinary team of experts. Assignment to a male or female gender is instantaneous when a baby is born. That this may not be possible in rare instances is immensely distressing to affected families. Indeed, abnormalities of the external genitalia sufficient to warrant genetic and endocrine studies occur in 1 in 4,500 births. There has been considerable progress in improved diagnosis and early management in recent decades, particularly with respect to congenital adrenal hyperplasia, the commonest cause of ambiguous genitalia of the newborn. For the purposes of this chapter, attention is focussed on the newborn with ambiguous genitalia and subsequent management in infancy and early childhood.

Androgen resistance

Androgen resistance causes the androgen insensitivity syndrome in its variant forms and is a paradigm of clinical syndromes associated with hormone resistance. In its complete form, the syndrome causes XY sex reversal and a female phenotype. Partial resistance to androgens is a common cause of ambiguous genitalia of the newborn, but a similar phenotype may result from several other conditions, including defects in testis determination and androgen biosynthesis. The biological actions of androgens are mediated by a single intracellular androgen receptor encoded by a gene on the long arm of the X chromosome. Mutations in this gene result in varying degrees of androgen receptor dysfunction and phenotypes that often show poor concordance with the genotype. Functional characterization and three-dimensional modelling of novel mutant receptors has been informative in understanding the mechanism of androgen action. Management issues in syndromes of androgen insensitivity include decisions on sex assignment, timing of gonadectomy in relation to tumour risk, and genetic and psychological counselling.

Regulation of Wolffian Duct Development

Wolffian ducts (WDs) are the embryonic structures that form the male internal genitalia. These ducts develop in both the male and female embryo. However, in the female they subsequently regress, whereas in the male they are stabilised by testosterone. The WDs then develop into separate but contiguous organs, the epididymis, vas deferens and seminal vesicles. Recently, considerable progress has been made in identifying genes that are involved in these different stages of development which is described in this review. In addition, WD development in (atypical forms of) cystic fibrosis and intersex disorders, such as the complete androgen insensitivity syndrome, 17beta-hydroxysteroid dehydrogenase deficiency and LH-receptor defects, is discussed. The apparent increase in male reproductive tract disorders is briefly discussed from the perspective of the potential endocrine-disrupting effects of the numerous chemicals in the environment to which the developing male foetus can be exposed.

Endocrine disrupting chemicals: a new and emerging public health problem?

Coordination of targeted toxicological studies is needed

A wider perspective on puberty

The mechanisms that control the onset of puberty remain within the purview of the neurobiologists who first recognised the concept of removal of a restraint factor to permit reawakening of puberty. The discovery of a ligand-activated G protein receptor-signalling pathway upstream of the GnRH pulse generator adds further weight to the role of the hypothalamus in the central regulation of puberty. The physical pointers to puberty are the mainstay of assessing timing and tempo in a clinical setting but non-invasive and indirect methods of assessment only are appropriate for population studies in normal children. That puberty can be regarded as a sensor recognises the observation of secular changes in pubertal timing and perhaps qualitative aspects of tempo. The influences on the sensor include marked changes in nutrition and an environmental exposure to low-dose chemical mixtures interacting with a polygenic background.

Consensus statement on management of intersex disorders

Management of intersex disorders

Consensus statement on management of intersex disorders

The birth of an intersex child prompts a long-term management strategy that involves a myriad of professionals working with the family. There has been progress in diagnosis, surgical techniques, understanding psychosocial issues and in recognizing and accepting the place of patient advocacy. The Lawson Wilkins Paediatric Endocrine Society (LWPES) and the European Society for Paediatric Endocrinology (ESPE) considered it timely to review the management of intersex disorders from a broad perspective, to review data on longer term outcome and to formulate proposals for future studies. The methodology comprised establishing a number of working groups whose membership was drawn from 50 international experts in the field. The groups prepared prior written responses to a defined set of questions resulting from an evidence based review of the literature. At a subsequent gathering of participants, a framework for a consensus document was agreed. This paper constitutes its final form.

Changes in Gene Expression during Wolffian Duct Development

BACKGROUND

Wolffian ducts (WDs) are the embryonic precursors of the male reproductive tract. Their development is induced by testosterone, which interacts with the androgen receptor (AR). The molecular pathways underlying androgen-dependent WD development are largely unknown. We aimed to identify AR target genes important in this process.

METHODS

RNA was isolated from rat WDs at E17.5 and E20.5. Affymetrix GeneChip expression arrays were used to identify transcripts up- or downregulated more than 2-fold. Regulation of seven transcripts was confirmed using quantitative PCR.

RESULTS

Transcripts from 76 known genes were regulated, including modulators of insulin-like growth factor and transforming growth factor-beta signalling. By controlling these modulators, androgens may indirectly affect growth factor signalling pathways important in epithelial-mesenchymal interactions and organ development. Caveolin-1, also upregulated, may play a role in modifying as well as mediating AR signalling. Differentiation of WD epithelium and smooth muscle, innervation and extracellular matrix synthesis were reflected in regulation of other transcripts. Several genes were previously suggested to be regulated by androgens or contained functional or putative androgen/glucocorticoid response elements, indicating they may be direct targets of androgen signalling.

CONCLUSION

Our results suggest novel cohorts of signals that may contribute to androgen-dependent WD development and provide hypotheses that can be tested by future studies.

Human androgen receptor gene ligand-binding-domain mutations leading to disrupted interaction between the N- and C-terminal domains

Most mutations in the androgen receptor (AR) ligand-binding domain (LBD) disrupt binding of the natural ligands: dihydrotestosterone and testosterone. Some AR LBD mutations do not affect ligand binding but they disrupt androgen-induced interaction of the N-terminal motif FXXLF and C-terminal activation function 2 (AF2). As N-/C-terminal interaction requires binding of agonists that have androgen activity in vivo, it correlates well with the phenotype. To study this further, we searched the Cambridge intersex database for patients with a detected missense mutation in the AR LBD presenting with normal ligand binding. Six mutations (D695N, Y763C, R774H, Q798E, R855H and L907F) were selected and introduced by site-directed mutagenesis into the pSVAR and pM-LBD plasmids. The transactivational potential of the wild-type and mutant androgen receptors (pSVAR) was examined by dual-luciferase assay using pGRE-LUC as a reporter vector. N-/C-terminal interaction was studied by mammalian two-hybrid assay using wild-type and mutated AR LBD (pM-LBD), pVP16-rAR-(5-538) (encoding rat amino-terminal AR) and pCMX-UAS-TK-LUC as a reporter. AR LBD mutations D695N, R774H and L907F presented with minimal transactivational capacity and N-/C-terminal interaction was totally disrupted. Mutations Y763C and R885H had some residual dose-dependent transactivational potential and minimal N-/C-terminal interaction. Q798E presented with good transactivational potential and it showed only mild reduction in N-/C-terminal interaction. With the selected mutations, N-/C-terminal interaction correlated well with AR transactivation and the phenotype. Disrupted N-/C-terminal interaction is capable of providing the mechanism for androgen-insensitivity syndrome in most cases where the mutation in the LBD does not disrupt ligand binding. Furthermore, mutations leading to the disrupted N-/C-terminal interaction can be localized to certain critical regions in the three-dimensional structure of the AR LBD. Our study shows that apart from the previously reported regions, regions just before helix 3, between helices 5 and 6, and at helix 10 are also important for AR N-/C-terminal interaction.

Five novel androgen receptor gene mutations associated with complete androgen insensitivity syndrome

Mutations in the androgen receptor (AR) gene result in androgen insensitivity syndrome (AIS). We have identified five novel mutations that result in a complete loss in AR function and are associated with complete AIS. The mutations span all three AR major functional domains. In two cases, the loss of AR function could be explained on the basis of the current knowledge of AR molecular structure and function. N-terminal mutation c.256C>T (p.Gln86X) leads to an early stop codon and abolishes all DNA and ligand binding. The DNA-binding domain mutation c.1685G>A (p.Cys562Tyr) is located in the N-terminal part of the first zinc finger; a mutation in this position is likely to impair the association of the mutated AR with the androgen response element of target genes. The splice site mutation at intron 2/exon 3 junction (c.1766-1G>A) is shown to lead to c.1765_1766 ins69 (p.[Gly589_Lys590ins23;Gly589Glu]). The two novel ligand-binding domain mutations identified were recreated by site-directed mutagenesis. Both mutations c.2171G>T (p.Gly724Val) and c.2435T>C (p.Leu812Pro) abolished AR ligand binding and severely impaired AR mediated transactivation. Residue p.Gly724 is located in the ligand binding domain, between helices 3 and 4. This region is known to be involved not only in ligand binding but also in AR N/C-terminal interactions. The mutation p.Leu812Pro is located in the C-terminal end of helix 8. This domain is highly conserved and critical for ligand binding. This study extends current understanding of AR mutations associated with CAIS.

Testicular development in the complete androgen insensitivity syndrome

The complete androgen insensitivity syndrome (CAIS), caused by mutations in the androgen receptor (AR) gene, is associated with abnormal testicular development and an increased risk of germ cell malignancy. Previous histological studies in CAIS have selected patients purely on the basis of clinical diagnosis and were mostly based on small numbers, many of whom were post-pubertal. Here, we present 44 cases of CAIS, each with molecular pathological confirmation of an AR mutation. The median age at gonadectomy was 5.5 years (5.5; IQR 1-13). We have been able, therefore, to investigate testicular development in infancy, childhood and puberty, and estimate the incidence of premalignant change in this series. In addition, we have investigated whether the presence of epididymides and/or vasa deferentia in CAIS, previously shown to be associated with residual activity of mutant ARs, is related to a particular testicular phenotype. Epididymides/vasa deferentia were present in 36% of cases and these patients showed varying degrees of seminiferous tubule maturation at puberty above those without epididymides/vasa deferentia (p = 0.003). There were no other histological differences between these patient groups. In both groups, features of testicular degeneration and dysgenesis were present and germ cell development was delayed, with prolonged expression of the gonocyte markers, placental-like alkaline phosphatase and activator protein-2gamma. Germ cell numbers rapidly declined after the first year of life (R(2) = 0.42). Only two cases of carcinoma in situ were identified in our study and both patients were postpubertal (17 and 53 years). From these results and the literature, we conclude that the risk of premalignant change in germ cells is low before and during puberty. Patients can be advised, therefore, that gonadectomy can be delayed to allow for a natural puberty, with low risk of malignant transformation. Our study only included one patient over 18 years, so we cannot comment on the risk of malignant transformation in later life.

Genetic mechanisms of fetal male undermasculinization: a background to the role of endocrine disruptors

Fetal male sex development proceeds along an orderly sequence of events coordinated by an interplay of genetic and hormonal events. These operate in a time- and concentration-dependent manner. Once a testis is formed (the female sex being constitutive in nature), differentiation of the internal and external male genitalia is androgen dependent. A number of genetic syndromes of sex reversal are well characterized at the biochemical and molecular levels. They fall into three principal categories: defects in formation of the testis, defects in production of androgens, and defects in the action of androgens. In many instances, the precise cause is not established, although the investigative evidence points in the direction of one of the three stated classifications. Polymorphic variants in several of the genes involved in male development are associated with certain degrees of male undermasculinization. While the genetic background is essentially static, it is plausible that the effect of endocrine disruptors during fetal life acting through epigenetic mechanisms may partly explain the observed changing trends in male reproductive tract disorders.

Inguinal hernia in female infants: a cue to check the sex chromosomes?

OBJECTIVES

To review the clinical presentation of complete androgen insensitivity syndrome (CAIS) and assess the current practice of considering the diagnosis of CAIS in female infants presenting with inguinal hernia.

PATIENTS AND METHODS

AIS arises from target tissue resistance to the actions of androgens due to molecular abnormalities in the androgen receptor. Patients with CAIS are born with normal external female genitalia, and although inguinal hernias are uncommon in female infants, they are a well-known presentation of CAIS. Such patients were identified from the Cambridge Intersex Database and details of presentation, presence and laterality of inguinal hernia and contents, and family history of CAIS, were recorded. A questionnaire detailing different indications for considering CAIS in female infants with a hernia was distributed to members of the British Association of Paediatric Surgeons and the British Society for Paediatric Endocrinology and Diabetes.

RESULTS

More than half of patients with CAIS presented with inguinal hernia, of which half were bilateral and a third contained gonads. Completed questionnaires were returned by 87 surgeons and 64 endocrinologists, and most of the surgeons and endocrinologists would consider CAIS in all female infants with a hernia. Bilateral hernias, hernias containing gonads and a family history of CAIS would prompt clinicians to consider the diagnosis.

CONCLUSION

Most clinicians agreed that CAIS should be considered in all female infants with inguinal hernia, as this is the commonest mode of presentation in childhood. Macroscopic inspection of the internal genital structures coupled, perhaps, with gonadal biopsy is recommended. Fluorescence in situ hybridization offers a rapid and reliable method to check the sex chromosomes. Liaison between the paediatric surgeon and endocrinologist is essential in management of infants with CAIS.

Correlation between genotype, phenotype and sex of rearing in 111 patients with partial androgen insensitivity syndrome

OBJECTIVE

Partial androgen insensitivity syndrome (PAIS) is a heterogeneous group of intersex disorders characterized by a typical perineoscrotal hypospadias/micropenis phenotype, and a normal androgen-producing testis. Various mutations in the androgen receptor (AR) are known to cause PAIS. Phenotypic expression is widely variable and there are no agreed guidelines to determine the sex of rearing in individuals with borderline masculinization. We aimed to quantitatively assess the external genital phenotype in relation to AR genotype and sex of rearing and identify criteria that differentiate mutation positive (ARmt) from mutation negative (ARwt) PAIS patients.

PATIENTS AND DESIGN

Cases with a diagnosis of PAIS were identified from the Cambridge Intersex Database. An external masculinization score (EMS) was used to quantify the degree of undermasculinization. Family history of AIS and details of the sex of rearing were recorded. Androgen binding was analysed in fibroblasts obtained from genital skin biopsies and mutational analysis of the AR was performed on genomic DNA extracted from peripheral blood. EMS and sex of rearing were compared in cases with similar mutations reported on the McGill International Database.

RESULTS

Two hundred and sixty-three patients with PAIS were identified. Androgen receptor gene sequencing was performed in 111 patients. Twenty-seven (24%) had mutations. Family history of AIS was present in 61 and 21% of ARmt and ARwt patients, respectively. The median EMS was 3 in both groups. The majority of ARmt patients had abnormal binding and there was a tendency to a higher median testosterone rise on hCG stimulation in ARmt (9.3 nmol/l) compared with ARwt patients (6.9 nmol/l). All patients with EMS of 4 or more were raised as male but there was an overlap of sex of rearing in patients with an EMS less than 4. A wide variation of EMS in relation to genotype and sex of rearing was observed.

CONCLUSION

The phenotype in PAIS is extremely variable and is rarely predicted by the AR genotype. Apart from the family history, there are no specific criteria to differentiate ARwt from ARmt. Sex of rearing is not entirely dependent on the EMS. Cultural issues, other modifying genes and response to androgen trials might be influencing factors. Collaborative studies with uniform protocols are needed to investigate infants with PAIS. Documenting phenotype, surgical procedures and outcome criteria are necessary to enable decision-making on the sex of rearing in patients with a lower range EMS.

A perspective on stem cells by a clinician

Stem cell terminology has entered the lexicon of medical practitioners even though the application of harvesting stem cells to treat diseases other than haematological disorders is not yet a reality in clinical practice. All branches of medicine will be affected by the new technology, more so those related to regenerative cell-based therapy for disorders such as Parkinson's disease, Alzheimer's disease, multiple sclerosis and traumatic injuries to the nervous system. Endocrinology is not a branch of medicine that carries a burden of disease that merits priority for the early application of stem cell therapy once the technique becomes safe and practical to do so. However, the allied disorder of diabetes is, sine qua non, an ideal example of how stem cell therapy has the potential to cure a chronic disabling condition. It is logical therefore to have included a number of articles on stem cells in this special issue of this journal, publishing papers on a range of endocrine-related topics.

Residual activity of mutant androgen receptors explains wolffian duct development in the complete androgen insensitivity syndrome

Development of the Wolffian ducts (WD) into epididymides and vasa deferentia is dependent on testosterone. Patients with the complete androgen insensitivity syndrome (CAIS) are therefore not expected to develop these structures. However, WD derivatives have been described in cases of CAIS. It is thought that these may be remnants. This study assesses the degree of WD development in 33 patients with CAIS and investigates whether this development was androgen dependent. Epididymides and vasa deferentia were identified in 70% of patients with substitution mutations in the androgen receptor ligand-binding domain. They were more developed than epididymides and vasa deferentia from 16- to 20-wk-old male fetuses, suggesting that the WD had been stimulated to grow, rather than failed to regress. Receptors with substitutions in the ligand-binding domain were normally expressed and showed residual response to androgens in transactivation assays. Patients with premature stop codons or frameshift mutations, which prevented androgen receptor expression, or DNA-binding domain mutations that abolished transcriptional activity did not have epididymides or vasa deferentia. We hypothesize that mutant receptors with residual activity in vitro respond to high local testosterone concentrations in vivo, thereby stimulating WD development. The classification of androgen insensitivity in such patients should be considered severe rather than complete.

Intersex and gender assignment; the third way?

The birth of a new baby is one of the greatest wonders of nature and one of the most exciting events known to man. The first question that is usually posed by the mother or father is "is it a boy or a girl?"; without this information the new parents cannot even formulate the second question which is usually "is he/she alright?". It is no wonder that the birth of a child with complex genital anomalies where the sex of rearing is uncertain at birth, presents difficult clinical and ethical issues.

Randomized, crossover comparison study of the short-term effect of oral testosterone undecanoate and intramuscular testosterone depot on linear growth and serum bone alkaline phosphatase

AIM

To compare the effects of oral testosterone undecanoate (TU) 40 mg daily and intramuscular depot sustanon 50 (SUS), 4 weekly, on short-term growth and bone turnover.

METHOD

Prospective, randomised, cross-over study over 26 weeks with 4 weeks of run-in, 8 weeks of treatment I (TU/SUS), 4 weeks of wash-out, 8 weeks of treatment II (SUS/TU) and 4 weeks of final wash-out.

MAIN OUTCOME MEASURES

Weekly change in lower leg length (LLL) as measured by knemometry, i.e. LLL velocity (LLLV) and absolute bone alkaline phosphatase levels (bALP), as well as percentage change in bALP (%bALP).

PATIENTS

Fourteen boys with delayed growth and puberty; two declined and one boy with sickle cell trait dropped out with priapism a week after SUS. The remainder had a median age of 14.3 years (range 12.5-17.4), testicular volume of 2 ml each (2-6), HtSDS of -2.1 (-3.3 to -1.0) and BA delay of 2.4 years (0.7-4.4).

RESULTS

Median LLLV in the treatment blocks was 0.7 mm/wk (-0.27 to 2.2) and LLLV during the run-in and wash-out periods was 0.27 mm/wk (-0.3 to 0.6) (p <0.005). LLLV during treatment with TU and SUS was 0.51 mm/wk (-0.22 to 2.17) and 0.67 mm/wk (-0.27 to 2.2), respectively (NS). Median LLLV during the washout phases that followed the TU block and the SUS block was similar at 0.28 mm/wk (-0.1 to 0.6) and 0.3 mm/wk (-0.2 to 0.6), respectively. LLLV peaks and troughs that were related to the timing of the injection were more evident during SUS therapy. Median bALP during the run-in period was 94.2 U/l (16-282) and the median %bALP during this period was 1.2% (-57, 16). The main rise in bALP occurred during the treatment blocks with a %bALP of 19.3% (-28.8, 121.7) (p <0.005). Median bALP at the beginning and end of the SUS block was 99.7 U/l (51.7, 225) and 170 U/l (64.8, 273), respectively (p <0.05). Median bALP at the beginning and end of the TU block was 111 U/l (51, 287) and 127.6 U/l (66.4, 298) (NS). Median %bALP during SUS was higher than during TU at 28.1% (4.4, 121.7) and 11.8% (-28.8, 83.6) (p = 0.07).

CONCLUSION

At the doses studied, testosterone undecanoate was as effective as sustanon at promoting short-term growth but changes in bone alkaline phosphatase were more marked during sustanon therapy.

Congenital adrenal hyperplasia: transitional care

Congenital adrenal hyperplasia (CAH) is a life-long disorder which poses management problems that are age- and sex-specific. The condition merits an organised, multi-disciplinary transitional care format similar to the kind that is now well established for Turner's syndrome in many centres. In the eyes of the paediatrician, achieving optimal growth is the primary target of CAH management during infancy and childhood. Fixation on this objective can be to the detriment of the patient because it may result in failure to appreciate the significance of metabolic disturbances that occur in later childhood, particularly in females, and which may be the progenitor of chronic problems with obesity, insulin resistance and infertility in adult life. Similarly, the care of the adult patient with CAH comprises more than just prescribing steroid replacement for primary adrenal insufficiency. The transition period between childhood and adulthood is an opportune time for review of the various management options and to assess the efficacy of steroid replacement, to consider alternative novel treatment modalities and to apply a checklist to the multi-faceted aspects of the medical, surgical and psychological needs of the patient.

Management of fetal endocrine disorders

A number of maternal endocrine disorders, when active during pregnancy, can have adverse effects on the newborn. Frequently, these affects can be anticipated as in Graves' disease, or the adverse effect can be prevented as in macrosomia in the infant of the diabetic mother. Occasionally, there are opportunities for prenatal treatment of a fetal endocrine disorder. For instance, a large goitre that may cause problems during delivery can be treated with thyroid hormones administered intra-amniotically or as analogues that cross the placenta. A uniquely effective form of treatment for prevention of a major birth defect is administration of dexamethasone to the mother to avoid virilisation of a female fetus with congenital adrenal hyperplasia (CAH). However, such treatment should only be conducted within the framework of a clinical trial as the long-term effects of exposure to potent glucocorticoids in utero are unknown. Intrauterine growth retardation, which affects about 5% of newborns, is currently not amenable to direct pharmacological treatment before birth. However, there are more practical options for managing this condition, including improved maternal nutrition and avoidance of toxins injurious to fetal growth.

Androgen receptor gene CAG repeat polymorphism in the development of ovarian hyperandrogenism

Ovarian hyperandrogenism, a key feature of polycystic ovary syndrome, is preceded by precocious pubarche (PP) (pubic hair < 8 yr) in some populations. We hypothesized that this earlier presentation may relate to increased androgen sensitivity, indicated by androgen receptor gene CAG repeat length. This polymorphism was genotyped in 181 Barcelona girls (age, 10.9 yr; range, 4-19 yr) who had presented with PP, and in 124 Barcelona control girls. PP girls had shorter mean CAG number than Barcelona controls (PP vs. controls: mean, range: 21.3, 7-31 repeats vs. 22.0, 15-32, P = 0.003) and greater proportion of short alleles 20 repeats or less (37.0% vs. 24.6%, P = 0.002). Among post-menarcheal PP girls (n = 69), shorter CAG number (biallelic mean </=20) was associated with higher 17-hydroxy-progesterone levels post leuprolide (P = 0.009), indicative of ovarian hyperandrogenism, higher testosterone levels (P = 0.02), acne (P = 0.03) and hirsutism scores (P = 0.01), and more menstrual cycle irregularities (P = 0.04). In multiple regression, ovarian hyperandrogenism risk was related to both low birth weight (SD <-1.5: odds ratio = 17.0; 95% confidence interval: 4.2-69.2) and shorter mean CAG number (20 or less repeats: odds ratio = 7.3; 1.3-42.0). In summary, shorter androgen receptor gene CAG number, indicative of increased androgen sensitivity, increases risks for PP and subsequent ovarian hyperandrogenism. Shorter CAG repeat alleles in Barcelona compared with United Kingdom women could lead to higher prevalences of these conditions.

Short-term effects of prednisolone and dexamethasone on circulating concentrations of leptin and sex hormone-binding globulin in children being treated for acute lymphoblastic leukaemia

OBJECTIVE

Disturbances in body weight regulation are often encountered during glucocorticoid treatment and are associated with increased insulin resistance and truncal fat accumulation. Children were investigated who were receiving glucocorticoid treatment for acute lymphoblastic leukaemia (ALL). They were randomized to receive either prednisolone or dexamethasone as part of induction of remission. This randomization process provided a suitable opportunity to compare the effects of these two administered steroid on surrogate markers of adipocyte activity (leptin) and hyperinsulinaemia/insulin resistance (SHBG).

DESIGN AND PATIENTS

Prospective study over 16 weeks of children randomized to receive prednisolone (40 mg/m2) or dexamethasone (6.5 mg/m2) as part of the MRC-ALL97/99 induction chemotherapy for ALL. Nineteen children (8 male, 11 female) with a median age 5.9 years (range 2.6-13 years) were recruited into the study. Main outcome measures were body mass index (BMI), serum leptin and sex hormone binding globulin (SHBG).

RESULTS

Glucocorticoid administration for 5 weeks resulted in significant (P < 0.05) increases in BMI, leptin (corrected for BMI) and the leptin : SHBG ratio and lowering of SHBG. Dose for dose, dexamethasone was significantly more potent than prednisolone in altering these parameters.

CONCLUSIONS

Short-term glucocorticoid treatment has significant effects on BMI, leptin and SHBG. The leptin : SHBG ratio increase indicates that this may be a novel and sensitive biochemical marker of metabolic change. Our results suggest that glucocorticoid treatment regimens should be kept as short as possible to avoid possible detrimental effects associated with increased adiposity and insulin resistance.

In-utero androgen exposure and 2nd to 4th digit length ratio-comparisons between healthy controls and females with classical congenital adrenal hyperplasia

BACKGROUND

Soft tissue measurements from the hand reveal lower second to fourth finger digit ratios (2D:4D) in males compared with females. The relatively longer 4th finger observed in males may be related to increased fetal exposure to androgens influencing the expression of Hox genes.

METHODS

We have measured 2D:4D ratios in 69 healthy females [median age 9.3 (range 1.9-17) years], 77 control males [median age 13.86 (2.1-20.3) years] and in 66 females with classical virilizing congenital adrenal hyperplasia (CAH) (median age 8.5 (1.1-16.2) years] who are known to be exposed to high concentrations of androgens in utero. Measurements were determined from X-rays of the left hand using vernier callipers. Intra-observer variability in measurement technique was 0.01%.

RESULTS

Control males had a significantly lower mean (SD) 2D:4D ratio [0.918 (0.029)] compared with female patients [0.927 (0.029), ANOVA P = 0.02]. No difference in 2D:4D ratio was observed between CAH females [0.925 (0.021)] and control females [0.927 (0.029)]. In contrast, 2D:4D ratio in males were significantly lower compared with CAH females (P = 0.03).

CONCLUSIONS

2D:4D ratios determined directly from radiographs of the left hand confirm significant differences between males and females. However, female patients with virilizing CAH do not have a male digit ratio pattern suggesting that in the left hand digit ratio development is not influenced by in-utero exposure to androgens.

Psychological outcomes and gender-related development in complete androgen insensitivity syndrome

We evaluated psychological outcomes and gender development in 22 women with complete androgen insensitivity syndrome (CAIS). Participants were recruited through a medical database (n = 10) or through a patient support group (n = 12). Controls included 14 males and 33 females, of whom 22 were matched to women with CAIS for age, race, and sex-of-rearing. Outcome measures included quality of life (self-esteem and psychological general well-being), gender-related psychological characteristics (gender identity, sexual orientation, and gender role behavior in childhood and adulthood), marital status, personality traits that show sex differences, and hand preferences. Women recruited through the database versus the support group did not differ systematically, and there were no statistically significant differences between the 22 women with CAIS and the matched controls for any psychological outcome. These findings argue against the need for two X chromosomes or ovaries to determine feminine-typical psychological development in humans and reinforce the important role of the androgen receptor in influencing masculine-typical psychological development. They also suggest that psychological outcomes in women with CAIS are similar to those in other women. However, additional attention to more detailed aspects of psychological well-being in CAIS is needed.

Reduced birth weight in boys with hypospadias: an index of androgen dysfunction?

Anthropometric birth measurements analysed for 51 boys with hypospadias identified in a prospective cohort study showed significant reductions in mean values for birth weight, length, and head circumference compared with controls. The absence of the usual sex dimorphism for these variables suggests that the results represent a marker of fetal androgen dysfunction in this subgroup of infants.

Short-term effects on linear growth and bone turnover in children randomized to receive prednisolone or dexamethasone

AIM

To compare the relative potency of prednisolone (Pred) and dexamethasone (Dex) on short-term growth and bone turnover.

METHOD

Prospective study over 16 weeks of children randomized to receive Pred (40 mg/m2) or Dex (6.5 mg/m2) for the first 5 weeks as part of the MRC-ALL97/99 induction chemotherapy for acute lymphoblastic leukaemia (ALL).

MEASUREMENTS

Lower leg length velocity (LLLV) and weight, serum IGF-I, serum bone alkaline phosphatase (bALP) levels and creatinine-adjusted, urinary excretion of deoxypyridinoline cross-links (DPD).

SUBJECTS

Nineteen children (eight boys, 11 girls) with a median age of 5.9 years (range 2.6-13) and with a diagnosis of ALL.

RESULTS

At week 2 of therapy, median LLLV in the Dex group was -1.5 mm/week (range 0.7 to -2.1) and significantly lower than the LLLV in the Pred group which was -0.1 mm/week (range 0.20 to -0.28; P < 0.05). In the Dex group, LLLV remained lower at week 8 (med LLLV, -0.3 mm/week, range 0 to -1.3) compared to LLLV in the Pred group at 0.3 mm/week (range 0.2-1.0; P < 0.05). Body weight showed an increase after week 2 and reached a peak in both groups of children at week 6. The change in weight from baseline was greater in the Dex group than the Pred group reaching a maximum change by week 5 of 17.5% (range 5-25) and 8.7% (range -3 to 18), respectively (P < 0.05). At presentation, median IGF-I level for the whole group was 83.5 micro g/l (range 31.8-293). IGF-I levels fell markedly during Dex therapy and continued to remain lower than baseline. At weeks 4, 6 and 8, median change in IGF-I from baseline was lower in the Dex group than the Pred group. From week 1 to week 3, median change in bALP was 72% (range -8 to 304) in the Pred group, whereas in the Dex group change in bALP was -1% (range 23 to -28; P < 0.005). By week 3, median bALP was higher in the Pred group at 65 U/l (range 36-187) than in the Dex group at 39 U/l (range 26-60; P < 0.05) but by week 6 median bALP in the Pred group had fallen to a similar level to the Dex group. At presentation, median DPD was 22 nmol/l (range 17-38) and 20 nmol/l (range 12-26) in the Pred and Dex groups, respectively (ns), reaching a nadir between weeks 3 and 6. The median percentage change in DPD in the Pred and Dex group from week 1 to week 3 was -34% (range -7 to 14) and -53% (range -6 to -69), respectively (ns). By week 8, DPD excretion had started to rise more dramatically in the Pred group such that the median DPD was 35 nmol/l (range 10-53) in the Pred group and 22 (range 9-30) in the Dex group (P < 0.05). On average, between weeks 2 and 8, LLLV was three times lower, percentage gain in weight was three times higher, bALP was 1.3 times lower and DPD was 1.5 times lower in the Dex group than the Pred group.

CONCLUSION

Pred and Dex both affect short-term growth and bone turnover. The mechanism of the effect on bone formation may be different between the two drugs. Dex may be about 18 times more potent than Pred at suppressing short-term linear growth and stimulating weight gain, and about nine times more potent at suppressing bone turnover. Glucocorticoids have a variable effect on different parameters of growth and bone turnover and the intensity may depend on the steroid used.

Congenital adrenal hyperplasia: 21-hydroxylase deficiency in the newborn and during infancy

Congenital adrenal hyperplasia is a family of monogenic autosomal recessive disorders of steroidogenesis with protean clinical manifestations. The commonest form, 21-hydroxylase deficiency, is the most frequent cause of ambiguous genitalia in the newborn. The molecular features associated with abnormalities in the CYP21 gene are well characterized in relation to phenotypic manifestations. The concordance between genotype and phenotype is sufficiently robust as to be relevant and useful in planning treatment strategies. Thus, the dose of glucocorticoid replacement in the early years of life can be tailored according to the predicted degree of 21-hydroxylase enzyme deficiency in the anticipation that this may avoid hitherto excessive steroid replacement during the critical early years of growth and development. The means to prevent genital virilization in affected females is clearly demonstrated by the success of early dexamethasone administration to pregnant mothers at risk. Short-term outcome studies of children exposed to dexamethasone in utero indicate no significant adverse effects. Nevertheless, it is recommended that prenatal treatment programs to prevent a major congenital malformation of the urogenital system be conducted only as part of agreed national multicenter studies, which include a commitment to long-term outcome analyses.

Evidence that luteinising hormone receptor polymorphisms may contribute to male undermasculinisation

BACKGROUND

The luteinising hormone receptor (LHR) is necessary for the stimulation of androgen production and male genital development. It contains three protein polymorphisms: a leucine and glutamine insertion between codons 8 and 9 (LQ+) and two amino acid substitutions (N291S, N312S).

OBJECTIVES

To determine whether these LHR polymorphisms are associated with male genital undermasculinisation or the androgen receptor polyglutamine repeat polymorphism (AR(Q)n), which contributes in some cases to the cause of genital undermasculinisation.

METHODS

The LHR polymorphisms were assessed by PCR amplification of genomic DNA, followed by restriction enzyme analysis. The frequency of the LHR polymorphisms were compared between an undermasculinised male group (n=75) and a control group (n=55).

RESULTS

LQ+ was not independently associated with the undermasculinised group (P=0.09), but it was associated with increased AR(Q)n within the undermasculinised group (P=0.02), particularly for AR(Q)n lengths >or=26 (P=0.002). In the undermasculinised group, homozygosity for N291 (872A/A) was more frequent (P=0.05), whereas homozygosity for N312 (935A/A) was less frequent (P=0.05). The combination of the presence of 872A/A and the absence of 935A/A showed a stronger association with the undermasculinised group than either polymorphism independently (P=0.006). The odds ratio of this genotype compared with any other, between the undermasculinised and control groups was 3.28 (95% confidence interval (CI) 1.33 to 8.08).

CONCLUSION

LHR polymorphisms may contribute to genital undermasculinisation.

Two de novo mutations in the AR gene cause the complete androgen insensitivity syndrome in a pair of monozygotic twins

The androgen insensitivity syndrome (AIS) is the most common cause of male undermasculinization and is typically caused by mutations in the AR gene. Affected individuals may exhibit either complete external feminization (complete AIS) or a partial phenotype (partial AIS). Here we describe monozygotic twins diagnosed with complete AIS who each possess two substitutions (C-->G at position 2930 and T-->C at position 2955, both in exon 7), leading to Phe(856)Leu and Ser(865)Pro mutations, respectively. Neither parent was found to be a carrier for these mutations, indicating that the double mutation arose de novo. Both mutations were recreated by site-directed mutagenesis and compared functionally with the wild-type receptor. The Phe(856)Leu mutation did not affect androgen binding when expressed in COS-1 cells, nor did this mutation decrease androgen-dependent trans-activation in transfected HeLa cells. However, the Ser(865)Pro mutation completely ablated androgen binding and trans-activation. In this study we demonstrate that the replacement of serine by proline at position 865 is sufficient in itself to cause complete AIS in these twins. Analyses of nuclear receptor structures suggest that this mutation is likely to perturb the conformation of helix 10/11, which plays a role in ligand binding, dimerization, and receptor activation. To our knowledge this is the first confirmed instance of AIS (complete or partial) due to an AR mutation occurring in twins. Furthermore, the phenotype was associated with two mutations that were both novel in nature.

The genetics of male undermasculinization

A review of the genetics of male undermasculinization must encompass a description of the embryology of the genital system. The dimorphism of sex development consequent upon the formation of a testis and the subsequent secretion of hormones to impose a male phenotype is highlighted. Thus, an understanding of the causes of male undermasculinization (manifest as XY sex reversal, complete and partial) includes reviewing the genetic factors which control testis determination and the production and action of testicular hormones. The study of disorders of male sex development has contributed substantially to knowledge of normal male development before birth. This knowledge has been complimented in recent years by the use of targeted murine gene disruption experiments to study the sex phenotype, although murine and human phenotypes are not always concordant. The investigation of disorders associated with male undermasculinization of prenatal onset is described briefly to complete the review.

Developmental aspects of androgen action

The formation of a testis from the indifferent gonad is the prelude to sequential steps in male sex differentiation orchestrated by time-dependent androgen biosynthesis and action. Information about the cellular and molecular mechanisms of androgen action can be obtained by the study of disorders of sex differentiation in males. The pivotal role of the androgen receptor as a ligand-induced transcription factor is emphasised and preliminary studies are described which attempt to identify developmentally regulated androgen-responsive genes. That androgen action can be modulated by gene polymorphisms is illustrated by the influence of an androgen receptor polyglutamine repeat in the multi-factorial causation of less severe forms of male under-masculinization.

Clinical and molecular evidence for the role of androgens and WT1 in testis descent

Testicular maldescent is a common congenital disorder associated with testicular cancer and infertility. In this study, testis position was assessed in subjects with genital abnormalities due to AR mutations, Denys-Drash and WAGR syndromes or an unknown aetiology. Subjects with completely female genitalia and an AR mutation or an unknown aetiology had a greater proportion of maldescended testes (intra-abdominal and inguinal) than those with less severe abnormalities (P=0.00027 and P<0.000001, respectively). Whereas subjects with severe, moderate or mild abnormalities and an unknown aetiology, had similar testis positions. The Denys-Drash and WAGR syndrome group had a greater proportion of maldescended testes than the AR mutation (P=0.013) and unknown aetiology groups (P=0.00019). Androgen production and AR binding were normal in three subjects with Denys-Drash and WAGR syndromes. These findings indicate that the relationship between testis descent and genital abnormalities is a multi-factorial process with greater complexity than previously proposed.

Autosomal recessive segregation of a truncating mutation of anti-Müllerian type II receptor in a family affected by the persistent Müllerian duct syndrome contrasts with its dominant negative activity in vitro

Anti-Müllerian hormone belongs to the TGFbeta family whose members exert their effects by signaling through two related serine/threonine kinase receptors. Mutations of the anti-Müllerian hormone type II receptor occur naturally, causing the persistent Müllerian duct syndrome. In a family with two members with persistent Müllerian duct syndrome and one normal sibling, we detected two novel mutations of the anti-Müllerian hormone type II receptor gene. One, transmitted by the mother to her three sons, is a deletion of a single base leading to a stop codon, causing receptor truncation after the transmembrane domain. The other, a missense mutation in the substrate-binding site of the kinase domain, is transmitted by the father to the two sons affected by persistent Müllerian duct syndrome, indicating a recessive autosomal transmission as in other cases of persistent Müllerian duct syndrome. Truncating mutations in receptors of the TGFbeta family exert dominant negative activity, which was seen only when each of the mutant anti-Müllerian hormone receptors was overexpressed in an anti-Müllerian hormone-responsive cell line. We conclude that assessment of dominant activity in vitro, which usually involves overexpression of mutant genes, does not necessarily produce information applicable to clinical conditions, in which mutant and endogenous genes are expressed on a one to one basis.

Minireview: sex differentiation

Mammalian sex differentiation is a hormone-dependent process in the male following the determination of a testis from the indifferent gonad through a cascade of genetic events. Female sex differentiation is not dependent on ovarian hormones, yet there is evidence that members of the Wnt family of developmental signaling molecules play a role in Müllerian duct development and in suppressing Leydig cell differentiation in the ovary. The testis induces male sex differentiation (including testis descent) through a time-dependent production of optimal concentrations of anti-Müllerian hormone, insulin-like factor(s) and androgens. Observations in several human syndromes of disordered fetal sex development corroborate findings in murine embryo studies, although there are exceptions in some gene knockout models. The ubiquitously expressed AR interacts in a ligand-dependent manner with coregulators to control the expression of androgen-responsive genes. Preliminary studies suggest the possibility of hormone resistance syndromes associated with coregulator dysfunction. Polymorphic variants in genes controlling androgen synthesis and action may modulate androgenic effects on sex differentiation.

Evidence that longer androgen receptor polyglutamine repeats are a causal factor for genital abnormalities

Moderate to severe undermasculinized genitalia was recently shown to be associated with longer polyglutamine repeats within the androgen receptor [AR(Gln)n]. However, it was unknown whether this was because longer AR(Gln)n contributed to the: 1) etiology; 2) severity; and/or 3) testicular maldescent. Therefore, AR(Gln)n length in 175 males with abnormal genitalia were analyzed according to etiology (known or unknown), severity (complete, severe, and moderate), or testis position (abdominal, inguinal, or scrotal). Etiology (P = 0.01) and severity (P = 0.02) but not testis position (P = 0.52) were associated with AR(Gln)n length. The association between the severity of the genital abnormalities and AR(Gln)n length was due to the close association of severity with the etiology (P < 0.0001). A highly selected group with moderate to severe genital abnormalities and multiple criteria to exclude known etiological factors had a greater AR(Gln)n length (mean, 25.33) than all other samples (mean, 23.11; P = 0.0004). The results suggest that AR(Gln)n length does not influence the severity of undermasculinization or testis descent but instead contributes to the causation of genital abnormalities in a subset of patients. These findings, together with a demonstrated relationship between severity and multifactorial etiology, are incorporated into a proposed model for the involvement of AR(Gln)n length in genital abnormalities.

Substitution mutation C268Y causes 17 beta-hydroxysteroid dehydrogenase 3 deficiency

The 17 beta-hydroxysteroid dehydrogenase (HSD) type 3 isozyme catalyzes the conversion of androstenedione to testosterone in the testis. Deleterious mutations in the HSD17B3 gene cause undermasculinization in genetic males attributable to impaired testosterone biosynthesis. Hence, a hallmark of this autosomal recessive disorder is a decreased plasma testosterone-to-androstenedione ratio. Here, a novel C268Y substitution mutation in exon 10 of the HSD17B3 gene, in a subject with 17 beta-HSD 3 deficiency, is reported. Reconstitution experiments with recombinant protein reveal that substitution of tyrosine for cysteine at position 268 of 17 beta-HSD type 3 abrogates the enzymatic activity. This finding brings to 20 the number of mutations in the HSD17B3 gene that cause male undermasculinization.

Genetic analysis of the INSL3 gene in patients with maldescent of the testis

OBJECTIVE

Testicular maldescent is important because it is a common congenital disorder that is associated with an increased risk of infertility and testicular cancer. Murine studies indicate that testicular maldescent can result from disruption of insulin-like factor 3 (INSL3) activity and that it may be more severe when there is concurrent undermasculinisation. Therefore, the INSL3 gene was screened for mutations and polymorphisms that may contribute to testicular maldescent in patients with undermasculinisation as well as those with isolated testicular maldescent.

METHODS AND RESULTS

The patient groups consisted of individuals with isolated testicular maldescent (n=28) and patients with undermasculinised genitalia and intra-abdominal (n=24) or inguinal gonads (n=33). The three control groups were: normal males (n=15), males with undermasculinised genitalia and scrotal gonads (n=29) and females (n=82). SSCP/HA mutation screening detected eight variants, five of which were predicted to alter the protein sequence (A-1G, V19L, P25S, A36T, R78H). Three of the amino acid changes (A-1G, V19L, R78H) each occurred in a single control sample and one was identified in a male with undermasculinised genitalia and intra-abdominal testes (P25S). The A36T amino acid polymorphism was found in both patient and control groups at a similar frequency.

CONCLUSIONS

The evidence suggests that INSL3 mutations and polymorphisms are not a major cause of testicular maldescent with or without associated undermasculinisation.