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Durval Damiani, Marc Fellous, Ken McElreavey, Sandrine Barbaux, Elenilde S A Barreto, Vaê Dichtchekenian and Nuvarte Setian

Abstract

Although true hermaphroditism (TH) accounts for less than 10% of intersex patients, it stands as a diagnostic challenge and has allowed a better understanding of the mechanisms involved in sexual differentiation. In this paper we review the clinical and laboratory data as well as molecular biology findings on 16 TH patients followed up at the Pediatric Endocrine Unit, Instituto da Criança, Hospital das Clínicas, São Paulo University Medical School. They were of a mean age of 3 years 8 months and nine of them were black. All the patients had ambiguous external genitalia as the main complaint. The 46,XX karyotype accounted for 50% of the cases and the ovotestis was the most frequent gonad found (59%). In the eight TH patients with a 46,XX karyotype, the sex-determining region of the Y chromosome (SRY) was negative, posing an intriguing question about the testicular differentiation mechanisms involved in these cases. In 7/19 ovotestes, the ovarian portion of the gonad has been preserved, keeping open the possibility of fertility. The female sex option was made in 10/16 cases (62·5%) and three patients exhibited spontaneous puberty. The mechanism through which testicular tissue develops without SRY has not yet been completely clarified, suggesting the involvement of the X chromosome as well as autosomal genes in the process.

European Journal of Endocrinology 136 201–204

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Sandrine Caburet, Ronit Beck Fruchter, Bérangère Legois, Marc Fellous, Stavit Shalev and Reiner A Veitia

Context

PCOS is a heterogeneous condition characterized by hyperandrogenism and chronic anovulation and affects about 10% of women. Its etiology is poorly known, but a dysregulation of gonadotropin secretion is one of its hallmarks.

Objective

As the etiology of PCOS is unclear, we have performed a genome-wide analysis of a consanguineous family with three sisters diagnosed with PCOS.

Methods

Whole-exome sequencing and Sanger sequencing confirmation.

Results

Whole-exome sequencing allowed the detection of the missense variant rs104893836 located in the first coding exon of the GNRHR gene and leading to the p.Gln106Arg (p.Q106R) substitution. Sanger sequencing of all available individuals of the family confirmed that the variant was homozygous in the three affected sisters and heterozygous in both parents.

Conclusions

This is the first description of a GNRHR gene mutation in patients diagnosed with PCOS. Although we do not exclude a possible interaction of the identified variant with the genetic background and/or the environment, our result suggests that genetic alterations in the hypothalamo–pituitary axis may play role in the pathogenesis of PCOS.

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Béatrice Mandon-Pépin, Philippe Touraine, Frédérique Kuttenn, Céline Derbois, Agnes Rouxel, Fumihiko Matsuda, Alain Nicolas, Corinne Cotinot and Marc Fellous

Objective

The goal of this study was to determine whether mutations of meiotic genes, such as disrupted meiotic cDNA (DMC1), MutS homolog (MSH4), MSH5, and S. cerevisiae homolog (SPO11), were associated with premature ovarian failure (POF).

Design

Case–control study.

Methods

Blood sampling, karyotype, hormonal dosage, ultrasound, and ovarian biopsy were carried out on most patients. However, the main outcome measure was the sequencing of genomic DNA from peripheral blood samples of 41 women with POF and 36 fertile women (controls).

Results

A single heterozygous missense mutation, substitution of a cytosine residue with thymidine in exon 2 of MSH5, was found in two Caucasian women in whom POF developed at 18 and 36 years of age. This mutation resulted in replacement of a non-polar amino acid (proline) with a polar amino acid (serine) at position 29 (P29S). Neither 36 control women nor 39 other patients with POF possessed this genetic perturbation. Another POF patient of African origin showed a homozygous nucleotide change in the tenth of DMC1 gene that led to an alteration of the amino acid composition of the protein (M200V).

Conclusions

The symptoms of infertility observed in the DMC1 homozygote mutation carrier and in both patients with a heterozygous substitution in exon 2 of the MSH5 gene provide indirect evidence of the role of genes involved in meiotic recombination in the regulation of ovarian function. MSH5 and DMC1 mutations may be one explanation for POF, albeit uncommon.

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Paul Laissue, Sophie Christin-Maitre, Philippe Touraine, Frederique Kuttenn, Olli Ritvos, Kristiina Aittomaki, Nathalie Bourcigaux, Laetitia Jacquesson, Philippe Bouchard, Rene Frydman, Didier Dewailly, Anne-Céline Reyss, Luke Jeffery, Anne Bachelot, Nathalie Massin, Marc Fellous and Reiner A Veitia

Background and objective: Mutations in bone morphogenic protein 15 (BMP15) and growth/differentiation factor 9 (GDF9) lead to altered fertility in animal models. In the human, a heterozygous point mutation of BMP15 has been associated with premature ovarian failure (POF).

Subject and methods: We have directly sequenced both genes in a cohort of 203 POF patients presenting with primary or secondary amenorrhea and high FSH levels and in a control population including 54 women with regular menstrual cycles who had at least one child.

Results: We have identified several heterozygous variants. One alteration in GDF9 (S186Y) and one in BMP15 (L148P) may have pathogenic effects as both positions are conserved in vertebrate species, ranging from the chicken to mammals. These variants were absent in the control samples. We also found synonymous and neutral substitutions.

Conclusions: We propose that although mutations in BMP15 and GDF9 are not a major cause of ovarian insufficiency, they may be involved in POF.