Background: Mayer-Rokitansky-Küster-Hauser (MRKH) syndrome, also referred to as Müllerian aplasia, is a congenital disorder characterized by aplasia of the uterus and upper part of the vagina in females with normal secondary sex characteristics and a normal female karyotype (46,XX). Main body: The diagnosis is often made during adolescence following investigations for primary amenorrhea and has an estimated prevalence of 1 in 5000 live female births. MRKH syndrome is classified as type I (isolated uterovaginal aplasia) or type II (associated with extragenital manifestations). Extragenital anomalies typically include renal, skeletal, ear, or cardiac malformations. The etiology of MRKH syndrome still remains elusive, however increasing reports of familial clustering point towards genetic causes and the use of various genomic techniques has allowed the identification of promising recurrent genetic abnormalities in some patients. The psychosexual impact of having MRKH syndrome should not be underestimated and the clinical care foremost involves thorough counselling and support in careful dialogue with the patient. Vaginal agenesis therapy is available for mature patients following therapeutical counselling and education with non-invasive vaginal dilations recommended as first-line therapy or by surgery. MRKH syndrome involves absolute uterine factor infertility and until recently, the only option for the patients to achieve biological motherhood was through gestational surrogacy, which is prohibited in most countries. However, the successful clinical trial of uterus transplantation (UTx) by a Swedish team followed by the first live-birth in September, 2014 in Gothenburg, proofed the first available fertility treatment in MRKH syndrome and UTx is now being performed in other countries around the world allowing women with MRKH syndrome to carry their own child and achieve biological motherhood. Conclusion: Several advances in research across multiple disciplines have been made in the recent years and this kaleidoscopic review provides a current status of various key aspects in MRKH syndrome and provides perspectives for future research and improved clinical care.

STUDY QUESTION What is the prevalence of Mayer–Rokitansky–Küster–Hauser (MRKH) syndrome? SUMMARY ANSWER The prevalence of MRKH syndrome in Denmark is 1 in 4982 (95% confidence interval (CI): 4216–5887) live female births. WHAT IS KNOWN ALREADY The prevalence of MRKH syndrome has been estimated to be around 1 in 4000–5000 females. However, population-based prevalence studies of MRKH syndrome are sparse. Moreover, population-based data on patient characteristics are lacking. STUDY DESIGN, SIZE, DURATION This retrospective cohort study used the Danish National Patient Registry (DNPR) to identify a nationwide population-based cohort of patients with MRKH syndrome. Subsequently, patients were linked to the Danish Cytogenetic Central Registry (DCCR) and patient medical records in order to validate the diagnoses. PARTICIPANTS/MATERIALS, SETTING, METHODS Hospitalizations and outpatient visits from 1994 to April 2015 at all public hospitals in Denmark were searched for patients assigned with a diagnosis code indicative of MRKH syndrome. The diagnoses were validated by diagnostic history in the DNPR and DCCR data, and by review of patient medical records. The prevalence was estimated considering the identified patients born from 1974 to 1996. Patient characteristics were described using data collected from DNPR, DCCR and patient medical records. MAIN RESULTS AND THE ROLE OF CHANCE The diagnosis was validated in 304 of 314 patients (96.8%) suspected with MRKH syndrome by review of diagnostic histories, DCCR data, and medical records and in 168 patients, the diagnosis of MRKH syndrome was confirmed (positive predictive value = 55.3% (95% CI: 49.5–60.9%)). The prevalence was 1 in 4982 (95% CI: 4216–5887) live female births based on 138 patients born from 1974 to 1996. Typical MRKH syndrome and atypical MRKH syndrome/Müllerian duct aplasia, Renal aplasia, and Cervicothoracic Somite dysplasia association were present in 56.5% and 43.5% of the patients, respectively. Kidney malformations were the most prevalent extragenital malformations, described in 38 of 111 patients (34.2%). However, in 57 patients (33.9%) no urinary tract imaging was performed. Three familial cases of MRKH syndrome were identified. LIMITATIONS, REASONS FOR CAUTION We identified all patients with MRKH syndrome diagnosed at public hospitals in Denmark. When interpreting the prevalence estimate, caution must be taken due to limitations such as patients not diagnosed in public hospitals, other diagnosis codes not used in the study and the unknown impact of a net positive migration rate in Denmark. WIDER IMPLICATIONS OF THE FINDINGS The prevalence estimate around 1 in 5000 is in accordance with a previous nationwide study. We consider the prevalence generalizable to other Caucasian populations. Prevalence studies of non-Caucasian populations are needed to investigate whether inter-ethnic differences in prevalence exist. Finally, the results of this study emphasize the need for sufficient basic examinations of patients with MRKH syndrome, including the importance of family medical history. STUDY FUNDING/COMPETING INTEREST(S) None.

Relapse is the leading cause of death of adult and pediatric patients with acute myeloid leukemia (AML). Numerous studies have helped to elucidate the complex mutational landscape at diagnosis of AML, leading to improved risk stratification and new therapeutic options. However, multi–whole-genome studies of adult and pediatric AML at relapse are necessary for further advances. To this end, we performed whole-genome and whole-exome sequencing analyses of longitudinal diagnosis, relapse, and/or primary resistant specimens from 48 adult and 25 pediatric patients with AML. We identified mutations recurrently gained at relapse in ARID1A and CSF1R, both of which represent potentially actionable therapeutic alternatives. Further, we report specific differences in the mutational spectrum between adult vs pediatric relapsed AML, with MGA and H3F3A p.Lys28Met mutations recurrently found at relapse in adults, whereas internal tandem duplications in UBTF were identified solely in children. Finally, our study revealed recurrent mutations in IKZF1, KANSL1, and NIPBL at relapse. All of the mentioned genes have either never been reported at diagnosis in de novo AML or have been reported at low frequency, suggesting important roles for these alterations predominantly in disease progression and/or resistance to therapy. Our findings shed further light on the complexity of relapsed AML and identified previously unappreciated alterations that may lead to improved outcomes through personalized medicine.

The aetiology of Mayer–Rokitansky–Küster–Hauser (MRKH) syndrome, characterized by uterovaginal agenesis in 46,XX women, remains poorly understood. Since familial occurrences are rare, genetic findings reported so far only apply to a minority of mainly sporadic cases and most studies have not included other family members enabling segregation analysis. Herein, we report on the investigation of a unique three-generation family of two female cousins with MRKH syndrome and unilateral renal agenesis (RA) and two deceased male relatives with RA. We performed whole-exome sequencing (WES) in eight family members leading to the identification of a novel pathogenic (CADD = 33) c.705G>T missense variant in GREB1L, a gene recently identified as a novel cause of RA. Previous reports include several cases of female fetuses with bilateral RA and uterus agenesis, which support GREB1L as an important gene in both kidney and female genital tract development. The pedigree is compatible with autosomal dominant inheritance with incomplete penetrance following a parent-origin-specific manner, which could be due to imprinting. To our knowledge, this is the first investigation of a larger MRKH syndrome pedigree using WES, and we suggest GREB1L as a novel and promising candidate gene in the aetiology of MRKH syndrome.

Numerous studies have been performed over the last decade to exploit the complexity of genomic and transcriptomic lesions driving the initiation of acute myeloid leukemia (AML). These studies have helped improve risk classification and treatment options. Detailed molecular characterization of longitudinal AML samples is sparse, however; meanwhile, relapse and therapy resistance represent the main challenges in AML care. To this end, we performed transcriptome-wide RNA sequencing of longitudinal diagnosis, relapse, and/or primary resistant samples from 47 adult and 23 pediatric AML patients with known mutational background. Gene expression analysis revealed the association of short event-free survival with overexpression of GLI2 and IL1R1, as well as downregulation of ST18. Moreover, CR1 downregulation and DPEP1 upregulation were associated with AML relapse both in adults and children. Finally, machine learning–based and network-based analysis identified overexpressed CD6 and downregulated INSR as highly copredictive genes depicting important relapse-associated characteristics among adult patients with AML. Our findings highlight the importance of a tumor-promoting inflammatory environment in leukemia progression, as indicated by several of the herein identified differentially expressed genes. Together, this knowledge provides the foundation for novel personalized drug targets and has the potential to maximize the benefit of current treatments to improve cure rates in AML.