Persistent Müllerian duct syndrome due to anti-Müllerian hormone receptor 2 microdeletions: a diagnostic challenge.

The persistent Müllerian duct syndrome (PMDS) is defined by the persistence of Müllerian derivatives in an otherwise normally virilized 46,XY male. It is usually caused by mutations in either the anti-Müllerian hormone (AMH) or AMH receptor type 2 (AMHR2) genes. We report the first cases of PMDS resulting from a microdeletion of the chromosomal region 12q13.13, the locus of the gene for AMHR2. One case involved a homozygous microdeletion of five exons of the AMHR2 gene. In the second case, the whole AMHR2 gene was deleted from the maternally inherited chromosome. The patient's paternal allele carried a stop mutation, which was initially thought to be homozygous by Sanger sequencing. Diagnostic methods are discussed, with an emphasis on comparative genomic hybridization and targeted massive parallel sequencing.

Pubertal growth spurt in patients with bilateral anorchia after testosterone replacement therapy.

Anorchia, the absence of testes in 46,XY boys, is a very rare condition. It has been suggested that the testicular tissue disappears during pregnancy, as a result of a vascular accident associated with torsion or a genetic cause. Because pubertal growth spurt is directly influenced by androgen exposure, we decided to evaluate the pubertal height gain in nine patients with anorchia who were followed up at the pediatric endocrinology unit of Bicêtre University Hospital. We retrospectively included nine patients with bilateral anorchia whose puberty had been induced by androgen replacement therapy and for whom final height measurements were available. Data were obtained from medical records. Mean gain in pubertal height was 21.7±2.3cm, lower than the expected gain during puberty (25cm, P<0.005). Despite limited experience in this rare condition, androgen replacement therapy seems to allow for good pubertal growth spurt in adolescents with anorchia. However, formal protocols for androgen therapy during puberty may need to be optimized.

NOBOX is a strong autosomal candidate gene in Tunisian patients with primary ovarian insufficiency.

Premature ovarian insufficiency (POI) affects approximately 1% of women before the age of 40. Genetic contribution is a significant component of POI. In this context, heterozygous mutations in NOBOX, BMP15 and GDF9 have been reported. The objective of our study was to evaluate the prevalence of these genes mutations in 125 unrelated Tunisian patients diagnosed with POI. The screening of NOBOX gene revealed three missense mutations (p.Arg117Trp; p.Gly91Trp and p.Pro619Leu) in eight patients. These mutations were not found in a 200 ethnically matched women without fertility problem. The sequencing of BMP15 and GDF9 gene revealed only previously reported variants. In contrast to previous studies, the prevalence of BMP15 variations is not higher than in the control population. Conversely, 6.4% of the cases present a NOBOX mutations; this high prevalence strengthens the consideration of NOBOX gene as strong autosomal candidate for POI.

SALL4 and NFATC2: two major actors of interstitial 20q13.2 duplication.

Interstitial duplication within the long arm of chromosome 20 is an uncommon chromosome structural abnormality. We report here the clinical and molecular characterization associated with pure 20q13.2 duplication in three unrelated patients. The most frequent clinical features were developmental delay, facial dysmorphism, cardiac malformation and skeletal anomalies. All DNA gains occurred de novo, ranging from 1.1 Mb to 11.5 Mb. Compared with previously reported conventional cytogenetic analyses, oligonucleotides array CGH allowed us to refine breakpoints and determine the genes of interest in the region. Involvement of SALL4 in cardiac malformations and NFATC2 gene disruption in both cardiac and skeletal anomalies are discussed.

Array comparative genomic hybridization analysis of small supernumerary marker chromosomes in human infertility.

Small supernumerary marker chromosomes (sSMC) are structurally abnormal chromosomes that cannot be unambiguously identified by conventional banding cytogenetics. This study describes four patients with sSMC in relation with infertility. Patient 1 had primary infertility. His brother, fertile, carried the same sSMC (patient 2). Patient 3 presented polycystic ovary syndrome and patient 4 primary ovarian insufficiency. Cytogenetic studies, array comparative genomic hybridization (CGH) and sperm analyses were compared with cases previously reported. sSMC corresponded to the 15q11.2 region (patients 1 and 2), the centromeric chromosome 15 region (patient 3) and the 21p11.2 region (patient 4). Array CGH showed 3.6-Mb gain for patients 1 and 2 and 0.266-Mb gain for patient 4. Sperm fluorescent in-situ hybridization analyses found ratios of 0.37 and 0.30 of sperm nuclei with sSMC(15) for patients 1 and 2, respectively (P < 0.001). An increase of sperm nuclei with disomy X, Y and 18 was noted for patient 1 compared with control and patient 2 (P < 0.001). Among the genes mapped in the unbalanced chromosomal regions, POTE B and BAGE are related to the testis and ovary, respectively. The implication of sSMC in infertility could be due to duplication, but also to mechanical effects perturbing meiosis.

Effect of NFE2L2 genetic polymorphism on the association between oral estrogen therapy and the risk of venous thromboembolism in postmenopausal women.

Oral, but not transdermal, estrogen therapy increases the risk of venous thromboembolism (VTE) in women who are past menopause. Data from the Estrogen and Thromboembolism Risk (ESTHER) study were used to investigate the effects of the genetic polymorphism of NFE2L2 rs6721961, which may impair Nrf2-dependent hepatic conjugation of estrogen metabolites. As compared with nonusers, the odds ratio (OR) for VTE in current users of oral estrogens was 2.5 (95% confidence interval (CI): 1.3-4.8) in patients with wild-type NFE2L2 and 17.9 (95% CI: 3.7-85.7) in those with the polymorphism (interaction, P = 0.01).

Congenital hypogonadotropic hypogonadism in females: clinical spectrum, evaluation and genetics.

Congenital hypogonadotropic hypogonadisms (CHH) are a well-known cause of pubertal development failure in women. In a majority of patients, the clinical spectrum results from an insufficient and concomitant secretion of both pituitary gonadotropins LH and FSH that impedes a normal endocrine and exocrine cyclical ovary functioning after the age of pubertal activation of gonadotropic axis. In exceptional but interesting cases, they can result from an elective deficit of one of the gonadotropins follicle-stimulating hormone (FSH) or luteinizing hormone (LH) by genetic anomaly of their specific ss sub-unit. CHH prevalence, estimated from teaching hospital series, is considered to be two to five fold less important in women compared to men bearing the disease. This frequency is probably under-estimated in reason of under-diagnosis of forms with partial pubertal development. Isolated or apparently isolated forms (i.e., Kallmann syndrome with anosmia or hyposmia not spontaneously expressed by the patients) of these diseases are most of the time discovered during adolescence or in adulthood in reason of lacking, incomplete or even apparently complete pubertal development, but with almost constant primary amenorrhea. In a minority of cases and mainly in familial forms, genetic autosomal causes have been found. These cases are related to mutations of genes impinging the functioning of the pituitary-hypothalamic pathways involved in the normal secretion of LH and FSH (mutations of GnRHR, GnRH1, KISS1R/GPR54, TAC3, TACR3), which are always associated to isolated non syndromic CHH without anosmia. Some cases of mutations of FGFR1, and more rarely of its ligand FGF8, or of PROKR2 or its ligand PROK2 have been shown in women suffering from Kallmann syndrome or its hyposmic or normosmic variant. In complex syndromic causes (mutations of CHD7, leptin and leptin receptor anomalies, Prader-Willi syndrome, etc.), diagnosis of the CHH cause is most often suspected or set down before the age of puberty in reason of the associated clinical signs, but some rare cases of paucisymptomatic syndromic causes can initially be revealed during adolescence, like isolated non syndromic CHH or Kallmann syndrome.

Elevated plasma ferritin and busulfan pharmacodynamics during high-dose chemotherapy regimens in children with malignant solid tumors.

Hepatic veno-occlusive disease (HVOD) is a frequent complication during hematopoietic stem-cell transplantation (HSCT). A strong relationship has been demonstrated between busulfan exposure and HVOD for busulfan-cyclophosphamide and allogeneic HSCT in adults. Busulfan disposition after the first intake was studied in 77 children treated for solid malignancies with high-dose busulfan-containing regimens and autologous HSCT. Busulfan was combined with cyclophosphamide and melphalan (n=30), melphalan (n=27), and thiotepa (n=20). No relationship was observed between busulfan exposure and HVOD. In contrast, plasma ferritin at baseline was higher in patients with HVOD (750 ng/ml (20-3,110)) compared with those without HVOD (189 ng/ml (8-3,967), P=0.012). Multivariate analysis showed that a ferritin level exceeding 300 ng/ml was the only risk factor for HVOD with an odds ratio of 4.0 (confidence interval 95% (1.5-11.2), P=0.0071). A high ferritin level at baseline was explained by the diagnosis of neuroblastoma, related treatments and transfusions.

In children and adolescents, the pharmacodynamics of high-dose busulfan is dependent on the second alkylating agent used in the combined regimen (melphalan or thiotepa).

A strong relationship has been demonstrated between high systemic exposure to busulfan and the occurrence of hepatic veno-occlusive disease (HVOD) after a busulfan-cyclophosphamide regimen (BU CY). We report a prospective study aimed at exploring the pharmacodynamics of high-dose busulfan combined with either melphalan (BU MEL) or thiotepa (BU TTP) followed by autologous stem cell transplantation in children and adolescents with a malignant solid tumor. Busulfan was given orally at a total dose of 600 mg m(-2). In all, 45 patients with a median age of 6.3 years were included in the study: 25 received BU MEL and 20 received BU TTP. The incidence of HVOD was 44% (CI 95% [23-65%]) in the BU MEL group and 25% (CI95% [9-49%]) in the BU TTP group. In the BU TTP group, patients who developed HVOD had a significantly higher AUC 0-6 h after the 13th dose (6201+/-607 h ng ml(-1)) than those who did not (5024+/-978 h ng ml(-1)) (P<0.05). In the BU MEL group, there was no difference in terms of systemic exposure to busulfan between patients who developed HVOD and those who did not. In conclusion, the guidelines established for monitoring BU CY cannot be extrapolated when busulfan is combined with another drug.