The genetic diagnosis of rare endocrine disorders of sex development and maturation: a survey among Endo-ERN centres

Disorders of sex development; Next-generation sequencing; Primary ovarian insufficiencyTrastornos del desarrollo sexual; Secuenciación de próxima generación; Insuficiencia ovárica primariaTrastorns del desenvolupament sexual; Seqüenciació de nova generació; Insuficiència ovàrica primàriaDifferences of sex development and maturation (SDM) represent a heterogeneous puzzle of rare conditions with a large genetic component whose management and treatment could be improved by an accurate classification of underlying molecular conditions, and next-generation sequencing (NGS) should represent the most appropriate approach. Therefore, we conducted a survey dedicated to the use and potential outcomes of NGS for SDM disorders diagnosis among the 53 health care providers (HCP) of the European Reference Network for rare endocrine conditions. The response rate was 49% with a total of 26 HCPs from 13 countries. All HCPs, except 1, performed NGS investigations for SDM disorders on 6720 patients, 3764 (56%) with differences of sex development (DSD), including 811 unexplained primary ovarian insufficiency, and 2956 (44%) with congenital hypogonadotropic hypogonadism (CHH). The approaches varied from targeted analysis of custom gene panels (range: 11–490 genes) in 81.5% of cases or whole exome sequencing with the extraction of a virtual panel in the remaining cases. These analyses were performed for diagnostic purposes in 21 HCPs, supported by the National Health Systems in 16 cases. The likelihood of finding a variant ranged between 7 and 60%, mainly depending upon the number of analysed genes or criteria used for reporting, most HCPs also reporting variants of uncertain significance. These data illustrate the status of genetic diagnosis of DSD and CHH across Europe. In most countries, these analyses are performed for diagnostic purposes, yielding highly variable results, thus suggesting the need for harmonization and general improvements of NGS approaches.This publication has been supported by Endo-ERN, which is co-funded by the European Union’s 3rd Health Programme (CHAFEA Framework Partnership Agreement No 739527)

The genetic diagnosis of rare endocrine disorders of sex development and maturation : a survey among Endo-ERN centres

Differences of sex development and maturation (SDM) represent a heterogeneous puzzle of rare conditions with a large genetic component whose management and treatment could be improved by an accurate classification of underlying molecular conditions, and next-generation sequencing (NGS) should represent the most appropriate approach. Therefore, we conducted a survey dedicated to the use and potential outcomes of NGS for SDM disorders diagnosis among the 53 health care providers (HCP) of the European Reference Network for rare endocrine conditions. The response rate was 49% with a total of 26 HCPs from 13 countries. All HCPs, except 1, performed NGS investigations for SDM disorders on 6720 patients, 3764 (56%) with differences of sex development (DSD), including 811 unexplained primary ovarian insufficiency, and 2956 (44%) with congenital hypogonadotropic hypogonadism (CHH). The approaches varied from targeted analysis of custom gene panels (range: 11-490 genes) in 81.5% of cases or whole exome sequencing with the extraction of a virtual panel in the remaining cases. These analyses were performed for diagnostic purposes in 21 HCPs, supported by the National Health Systems in 16 cases. The likelihood of finding a variant ranged between 7 and 60%, mainly depending upon the number of analysed genes or criteria used for reporting, most HCPs also reporting variants of uncertain significance. These data illustrate the status of genetic diagnosis of DSD and CHH across Europe. In most countries, these analyses are performed for diagnostic purposes, yielding highly variable results, thus suggesting the need for harmonization and general improvements of NGS approaches.publishersversionPeer reviewe

STK11 gene mutations among patients with sporadic breast cancer

Germline mutations affecting STK11 (LRG_319) are profoundly studied in relation to Peutz-Jeghers syndrome, predisposing to the development of various cancers at multiple sites. Though somatic mutations in STK11 are found to be present in several cancers, limited data on its involvement in sporadic breast cancer are available. The present study aims to evaluate the frequency and spectrum of genetic alterations in STK11 in a group of Bulgarian patients with sporadic breast cancer. A total of 73 tumor and 22 corresponding blood specimens derived from the patients, and 10 blood samples from clinically healthy controls were analyzed. High Resolution Melting analysis followed by Sanger sequencing and bioinformatic prediction tools were utilized. Seven patients (9.58%) harbored STK11 alterations, only two (2.74%) of which are exonic: one nonsense c.322A>T; p.K108X (deleterious) and one missense c.440G>A; p.Arg147His (of unknown significance). Two intronic variants were also observed: c.290+36G>T and c. *16+18C>A (novel). To our knowledge the results represent the first data indicating presence of STK11 alterations in patients with sporadic breast cancer. The limited number of the detected deleterious mutations indicates that mutational inactivation of the gene is a rare event and probably plays a minor role in sporadic breast carcinogenesis

SCN8A p.Arg1872Gln mutation in early infantile epileptic encephalopathy type 13: Review and case report

Early infantile epileptic encephalopathy (EIEE) is a disorder with variable genetic heterogeneity. Symptoms are mostly presented with generalised epileptic seizures with an infantile onset and progressive neurodevelopmental delay. Early infantile epileptic encephalopathy13 is caused by mutations in the SCN8A gene, which encodes the neuronal voltage-gated sodium channel α subunit (Nav1.6) and plays a major role in neuronal excitability. Describing the wide clinical variability of previously reported cases of patients carrying the same mutation, we demonstrate the complexity of the disease and the necessity of correctly correlating the phenotype with the genotype. Here, we present a minireview and a case report of EIEE13 involving the rare p.Arg1872Gln mutation in the SCN8A gene. We used targeted next-generation sequencing to examine a six-year-old girl with complex partial seizures from the left temporal lobe since 4 months of age. The condition was difficult to control with medication and the seizures evolved to generalised tonic-clonic seizures after the age of 3 years. Neurodevelopment in the child became severely delayed although seizures were as rare as 1 in every 5–10 months. А heterozygous missense mutation in the SCN8A gene (NM_014191.3:c.5616G > A, NP_055006.1:p.Arg1872Gln) was found. The variant was validated by Sanger sequencing. We suggest that this SCN8A mutation has a primary neurodegenerative effect leading to brain atrophy and intellectual disability (with or without autism) that is partially independent of its epileptogenic effect. Our results demonstrate that the application of large panels with clinically-associated genes is essential for identifying rare mutations in individuals with disorders of unknown etiology

The genetic diagnosis of rare endocrine disorders of sex development and maturation: a survey among Endo-ERN centres

Differences of sex development and maturation (SDM) represent a heterogeneous puzzle of rare conditions with a large genetic component whose management and treatment could be improved by an accurate classification of underlying molecular conditions, and next-generation sequencing (NGS) should represent the most appropriate approach. Therefore, we conducted a survey dedicated to the use and potential outcomes of NGS for SDM disorders diagnosis among the 53 health care providers (HCP) of the European Reference Network for rare endocrine conditions. The response rate was 49% with a total of 26 HCPs from 13 countries. All HCPs, except 1, performed NGS investigations for SDM disorders on 6720 patients, 3764 (56%) with differences of sex development (DSD), including 811 unexplained primary ovarian insufficiency, and 2956 (44%) with congenital hypogonadotropic hypogonadism (CHH). The approaches varied from targeted analysis of custom gene panels (range: 11–490 genes) in 81.5% of cases or whole exome sequencing with the extraction of a virtual panel in the remaining cases. These analyses were performed for diagnostic purposes in 21 HCPs, supported by the National Health Systems in 16 cases. The likelihood of finding a variant ranged between 7 and 60%, mainly depending upon the number of analysed genes or criteria used for reporting, most HCPs also reporting variants of uncertain significance. These data illustrate the status of genetic diagnosis of DSD and CHH across Europe. In most countries, these analyses are performed for diagnostic purposes, yielding highly variable results, thus suggesting the need for harmonization and general improvements of NGS approaches