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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., (© The Author(s) 2020. Published by Oxford University Press on behalf of the European Society of Human Reproduction and Embryology. All rights reserved. For permissions, please e-mail: journals.permission@oup.com.)

Context: Mutations in DAX1 (dosage-sensitive sex reversal-adrenal hypoplasia congenita critical region on the X chromosome gene 1; NR0B1) cause X-linked adrenal hypoplasia congenita, a disease characterized by primary adrenal failure, testicular dysgenesis, and gonadotropin deficiency. Most DAX1 mutations are deletions, nonsense, or frameshift mutations that markedly impair its transcriptional activity. Missense mutations have been restricted to the carboxy-terminal domain and are associated with more variable clinical phenotypes., Objective: The objective was to identify novel clinical phenotypes associated with DAX1 missense mutations., Patients and Design: We investigated the genetic basis of isolated mineralocorticoid deficiency in a patient who carries a unique missense mutation (W105C) in the amino-terminal region of DAX1., Results: The W105C DAX1 mutation in the proband was present in three asymptomatic hemizygous males, but it was not detected in the general population. Using in vitro studies of DAX1 expression and function in transfected cells, we demonstrate that the mutant DAX1 protein exhibits mild loss of function, whether studied for genes it represses or for genes it activates. Structure-function studies suggest that the W105C and other mutations in the aminoterminus are compensated by the presence of repeated LXXLL motifs that mediate DAX1 interactions with other proteins., Conclusions: We describe the first missense mutation in the aminoterminus of DAX1 and conclude that mutations in this region may be partially compensated by redundant functional domains. Mild DAX1 mutations may be a cause of isolated mineralocorticoid deficiency.

Couples dealing with microdeletions of the Y chromosome have to make decisions about their reproductive future. Do they opt for intracytoplasmic sperm injection (ICSI), artificial insemination with donor insemination (AID) or no treatment? We analysed this decision in 28 couples and investigated the role of the counsellor and the counselling process on the final decision of the couple. Ten counsellors from six fertility clinics in The Netherlands and Belgium were interviewed about their genetic counselling of couples dealing with microdeletions. The answers to the questionnaire were converted to 11 dichotomous variables. Of the 1627 tested men in the six centres, 37 (2.3%) had a microdeletion in the AZFc region, a subregion of the AZF region on the Y chromosome important for normal spermatogenesis. The decisions of 28 of them could be analysed. Most couples chose ICSI (79%). The remaining couples chose donor insemination (7%) or refrained from treatment (14%). Several variables, including the counselling procedure, the counsellor and the available treatments in the fertility centre, influenced the decision of the couple. In conclusion, most couples dealing with microdeletions in the AZF region choose ICSI. Several aspects of the process of genetic counselling appear to be related to the final decision.

A follow-up study was performed to investigate the impact of the detection of a chromosome abnormality in infertile men who are candidates for intracytoplasmic sperm injection (ICSI) treatment. In this collaborative study between clinical genetics centres and fertility clinics in the Netherlands, 75 ICSI couples of which the male partners had a chromosome abnormality were included. All couples were extensively counselled on the risk of having a chromosomally unbalanced child. Forty-two out of 75 couples chose to proceed with the ICSI treatment. So far, treatment has resulted in a pregnancy in 11 cases. Four of them opted to have invasive prenatal diagnosis. Despite the genetic risks related to a chromosome abnormality in infertile men, a small majority (56%) of the couples did not refrain from the ICSI treatment.

A balanced translocation t(Y;16)(q11.21;q24) is described in a male with severe oligoasthenoteratozoospermia (OAT). Before having a chromosome investigation, the patient and his partner had undergone intracytoplasmic sperm injection (ICSI) treatment resulting in the birth of a healthy 46,XX child. After detection of the t(Y;16) translocation, the couple opted for further ICSI treatment, although they were extensively counselled on the risk of having chromosomally unbalanced offspring. This treatment resulted in a twin pregnancy, one with a 46,XX karyotype and the other a 46,X,t(Y;16) (q11.21;q24) karyotype, the same as the father. After an uncomplicated pregnancy two healthy children were born. We conclude that patients with a Y/autosome translocation as a cause of OAT can have chromosomally normal children after ICSI treatment.