Changes in the clinical management of 5α-reductase type 2 and 17ß-hydroxysteroid dehydrogenase type 3 deficiencies in France.

Objectives: To examine the changes in diagnostic practices and clinical management of patients with 5α-reductase type 2 (SRD5A2) or 17ß-hydroxysteroid dehydrogenase type 3 (HSD17B3) deficiency since molecular diagnoses became available. Methods: Clinical, laboratory, and therapeutic data were retrieved from the medical records of 52 patients with a molecular diagnosis of SRD5A2 (n = 31) or HSD17B3 (n = 21) deficiency. Temporal trends regarding age at assessment and initial sex assignment over 1994-2020 were qualitatively analyzed. Age at molecular diagnosis was compared between two subgroups of patients according to their year of birth. Results: Fifty-eight percent (n = 30) patients were diagnosed during the perinatal period, 33% (n = 17) during infancy, and 9% (n = 5) during adolescence or adulthood. Over the studied period, the patients' age at initial assessment and diagnosis frankly decreased. The median (range) age at diagnostic confirmation was 10.5 (0-53.2) years for patients born before 2007 and 0.4 (0-9.3) years for those born in 2007 or later (P = 0.029). Genetic testing identified 27 different variants for the SRD5A2 gene (30% novel, n = 8) and 18 for the HSD17B3 gene (44% novel, n = 8). Before 2002, most patients were initially assigned as females (95%, n = 19), but this proportion dropped for those born later (44%, n = 14; P < 0.001). The influence of initial genital appearance on these decisions seemingly decreased in the most recent years. Therapeutic interventions differed according to the sex of rearing. Ten percent (n = 2) patients requested female-to-male reassignment during adulthood. Conclusion: This study showed, over the past two decades, a clear trend toward earlier diagnosis and assignment of affected newborns as males.

Mayer-Rokitansky-Künster-Hauser syndrome due to 2q12.1q14.1 deletion: PAX8 the causing gene?

Mayer-Rokitansky-Küster-Hauser syndrome (MRKH) is a rare malformative disorder, characterized by congenital aplasia of the uterus and the upper two thirds of the vagina (MIM #277000). For a majority of patients, the disorder remained without identified genetic cause. However, four recurrent microdeletions, i.e. 1q21.1-16p11.2-17q12 and 22q11.21, as well as variants in genes contained in these loci, have been identified in a small number of cases. We describe an additional patient with 2q12.1q14.1 microdeletion, showing MRKH and congenital hypothyroidism due to thyroid gland hypoplasia. The patient received a dual diagnosis with microdeletion of SHOX locus in addition to the 2q12.1q14.1 microdeletion. Literature review and database analysis has enabled us to identify 5 OMIM morbid genes: CKAP2L, IL1B, IL1RN, IL36RN and PAX8. Among these, PAX8 (Paired Box Gene 8), a transcriptional factor part of the paired-box family, plays a key role in the development of the thyroid gland, kidneys and Müllerian derivatives. We discuss here the role of PAX8 and speculate on the possible involvement of PAX8 in MRKH. In this study, we report a second case of 2q12.1q14.1 microdeletion, involving PAX8 as a gene associated with Müllerian agenesis in a MRKH I and hypothyroidism. Further studies will confirm the direct participation of PAX8 in gene target sequencing in a population of MRKH with hypothyroidism.

Reversion SAMD9 Mutations Modifying Phenotypic Expression of MIRAGE Syndrome and Allowing Inheritance in a Usually de novo Disorder.

Context: MIRAGE (Myelodysplasia, Infection, Restriction of growth, Adrenal hypoplasia, Genital phenotypes, Enteropathy) syndrome is a severe multisystem disorder with high mortality. It is caused by a heterozygous gain of function mutation in the growth repressor gene SAMD9. The increasing number of reported cases displays a spectrum of phenotypes that may be explained by an adaptation mechanism, with appearance of a somatic second hit mutation with revertant effects. Objective: To determine the genetic basis of the MIRAGE syndrome rapidly corrected in a living and healthy 46,XY patient. Subjects and Methods: A 46,XY patient born with growth restriction and disorders of sex development had thrombocytopenia and necrotizing enterocolitis during the neonatal period suggestive of the syndrome. Faced with the rapid improvement of the patient's phenotype, an adaptation mechanism was sought by repeating genetic analysis at different ages; her parents also underwent genetic analysis. Results: The previously described p.(Thr778Ile) mutation was identified and surprisingly transmitted by the asymptomatic mother in this usually de novo syndrome. To explain the rapid improvement of the patient's phenotype and absence of symptoms in the mother, an adaptation mechanism was sought. For the mother, a non-sense mutation was found (p.(Arg221*)) in cis, and most likely appeared in utero. It was not transmitted to her child. The child harbored a different non-sense mutation (p.(Arg285*)) that most likely appeared near day 20. Conclusions: We show that pathogenic variants can be inherited from a healthy parent as the adaptation mechanism may arise early in life and mask symptoms. Presence of revertant mosaicism mutations could explain "incomplete penetrance" in other disease. For a better management and outcomes in patients, appearance of this natural gene therapy should be sought by repeating genetic analysis.

Surgery in disorders of sex development (DSD) with a gender issue: If (why), when, and how?

Ten years after the consensus meeting on disorders of sex development (DSD), genital surgery continues to raise questions and criticisms concerning its indications, its technical aspects, timing and evaluation. This standpoint details each distinct situation and its possible management in 5 main groups of DSD patients with atypical genitalia: the 46,XX DSD group (congenital adrenal hyperplasia); the heterogeneous 46,XY DSD group (gonadal dysgenesis, disorders of steroidogenesis, target tissues impairments …); gonosomic mosaicisms (45,X/46,XY patients); ovo-testicular DSD; and "non-hormonal/non chromosomal" DSD. Questions are summarized for each DSD group with the support of literature and the feed-back of several world experts. Given the complexity and heterogeneity of presentation there is no consensus regarding the indications, the timing, the procedure nor the evaluation of outcome of DSD surgery. There are, however, some issues on which most experts would agree: 1) The need for identifying centres of expertise with a multidisciplinary approach; 2) A conservative management of the gonads in complete androgen insensitivity syndrome at least until puberty although some studies expressed concerns about the heightened tumour risk in this group; 3) To avoid vaginal dilatation in children after surgical reconstruction; 4) To keep asymptomatic mullerian remnants during childhood; 5) To remove confirmed streak gonads when Y material is present; 6) It is likely that 46,XY cloacal exstrophy, aphallia and severe micropenis would do best raised as male although this is based on limited outcome data. There is general acknowledgement among experts that timing, the choice of the individual and irreversibility of surgical procedures are sources of concerns. There is, however, little evidence provided regarding the impact of non-treated DSD during childhood for the individual development, the parents, society and the risk of stigmatization. The low level of evidence should lead to design collaborative prospective studies involving all parties and using consensual protocols of evaluation.

Surgical options in disorders of sex development (dsd) with ambiguous genitalia.

Disorders of sexual development (DSD) include three main groups of patients: (1) The virilised 46,XX DSD essentially represented by congenital adrenal hyperplasia (CAH) ; (2) The undervirilised 46,XY DSD essentially represented by hypospadias; and (3) the chromosomic jigsaws essentially represented by mixed gonadal dysgenesis. It is in this last group that gender assignment remains a difficult decision involving various indicators, which can be split into four categories: (1) the inside sex (i.e., genes, hormones and target tissues); (2) the outside sex (i.e., anatomy of genitalia including size of the genital tubercle, mullerian cavity and potential adult height of the patient); (3) the functional sex (i.e., potential sexuality and fertility); and (4) and the social sex (i.e., the cultural medium in which the child is brought up). The challenge is to outline the future individual identity of the child in the postnatal period using these indicators. Current evolutions of surgical techniques of 'feminisation' and 'masculinisation' are described as well as their outcomes.