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Objective Growth hormone insensitivity (GHI) encompasses growth restriction, normal/elevated growth hormone (GH), and low insulin-like growth factor I (IGF1). “Nonclassical” GHI is poorly characterized and is rarely caused by heterozygous dominant-negative (DN) variants located in the intracellular or transmembrane domains of the GH receptor (GHR). We sought to determine the molecular mechanisms underpinning the growth restriction in 2 GHI cases. Methods and Design A custom-made genetic investigative pipeline was exploited to identify the genetic cause of growth restriction in patients with GHI. Nanoluc binary technology (NanoBiT), in vitro splicing assays, western blotting, and flow cytometry, characterized the novel GHR variants. Results Novel heterozygous GHR variants were identified in 2 unrelated patients with GHI. In vitro splicing assays indicated both variants activated the same alternative splice acceptor site resulting in aberrant splicing and exclusion of 26 base pairs of GHR exon 9. The GHR variants produced truncated receptors and impaired GH-induced GHR signaling. NanoBiT complementation and flow cytometry showed increased cell surface expression of variant GHR homo/heterodimers compared to wild-type (WT) homodimers and increased recombinant human GH binding to variant GHR homo/heterodimers and GH binding protein (GHBP) cleaved from the variant GHRs. The findings demonstrated increased variant GHR dimers and GHBP with resultant GH sequestration. Conclusion We identified and characterized 2 novel, naturally occurring truncated GHR gene variants. Intriguingly, these DN GHR variants act via the same cryptic splice acceptor site, highlighting impairing GH binding to excess GHBP as a potential therapeutic approach.

Most aldosterone-producing adenomas (APAs) have gain-of-function somatic mutations of ion channels or transporters. However, their frequency in aldosterone-producing cell clusters of normal adrenal gland suggests a requirement for codriver mutations in APAs. Here we identified gain-of-function mutations in both CTNNB1 and GNA11 by whole-exome sequencing of 3/41 APAs. Further sequencing of known CTNNB1-mutant APAs led to a total of 16 of 27 (59%) with a somatic p.Gln209His, p.Gln209Pro or p.Gln209Leu mutation of GNA11 or GNAQ. Solitary GNA11 mutations were found in hyperplastic zona glomerulosa adjacent to double-mutant APAs. Nine of ten patients in our UK/Irish cohort presented in puberty, pregnancy or menopause. Among multiple transcripts upregulated more than tenfold in double-mutant APAs was LHCGR, the receptor for luteinizing or pregnancy hormone (human chorionic gonadotropin). Transfections of adrenocortical cells demonstrated additive effects of GNA11 and CTNNB1 mutations on aldosterone secretion and expression of genes upregulated in double-mutant APAs. In adrenal cortex, GNA11/Q mutations appear clinically silent without a codriver mutation of CTNNB1. Sequence analysis identifies gain-of-function somatic mutations in GNA11 or GNAQ in CTNNB1-mutant aldosterone-producing adenomas. Most patients with these mutations presented during puberty, pregnancy or menopause, with elevated LHCGR expression.

Context Severe forms of growth hormone insensitivity (GHI) are characterized by extreme short stature, dysmorphism, and metabolic anomalies. Objective This work aims to identify the genetic cause of growth failure in 3 “classical” GHI individuals. Methods A novel intronic growth hormone receptor gene (GHR) variant was identified, and in vitro splicing assays confirmed aberrant splicing. A 6Ω pseudoexon GHR vector and patient fibroblast analysis assessed the consequences of the novel pseudoexon inclusion and the impact on GHR function. Results We identified a novel homozygous intronic GHR variant (g.5:42700940T > G, c.618+836T > G), 44 bp downstream of the previously recognized intronic 6Ψ GHR pseudoexon mutation in the index patient. Two siblings also harbored the novel intronic 6Ω pseudoexon GHR variant in compound heterozygosity with the known GHR c.181C > T (R43X) mutation. In vitro splicing analysis confirmed inclusion of a 151-bp mutant 6Ω pseudoexon not identified in wild-type constructs. Inclusion of the 6Ω pseudoexon causes a frameshift resulting in a nonfunctional truncated GHR lacking the transmembrane and intracellular domains. The truncated 6Ω pseudoexon protein demonstrated extracellular accumulation and diminished activation of STAT5B signaling following GH stimulation. Conclusion Novel GHR 6Ω pseudoexon inclusion results in loss of GHR function consistent with a severe GHI phenotype. This represents a novel mechanism of Laron syndrome and is the first deep intronic variant identified causing severe postnatal growth failure. The 2 kindreds originate from the same town in Campania, Southern Italy, implying common ancestry. Our findings highlight the importance of studying variation in deep intronic regions as a cause of monogenic disorders.

BackgroundTime in general practice offers medical students opportunities to learn a breadth of clinical knowledge and skills relevant to their future clinical practice. Undergraduate experiences shape career decisions and current recommendations are that 25% of undergraduate curriculum time should be focused on general practice. However, previous work demonstrated that GP teaching had plateaued or reduced in UK medical schools. Therefore, an up-to-date description of undergraduate GP teaching is timely.AimTo describe the current picture of UK undergraduate GP teaching, including the amount of time and resources allocated to GP teaching.Design and settingA cross-sectional questionnaire study across 36 UK medical schools.MethodThe questionnaire was designed based on a previous survey performed in 2011–2013, with additional questions on human and financial support allocated to GP teaching. The questionnaire was piloted and revised prior to distribution to leads of undergraduate GP teaching in UK medical schools.ResultsThe questionnaire response rate was 100%. GP teaching constituted an average of 9.2% of medical curricula; this was lower than previous figures, though the actual number of GP sessions has remained static. The majority (n = 23) describe plans to increase GP teaching in their local curricula over the next 5 years. UK-wide average payment was 55.60 GBP/student/session of in-practice teaching, falling well below estimated costs to practices. Allocation of human resources was varied.ConclusionUndergraduate GP teaching provision has plateaued since 2000 and falls short of national recommendations. Chronic underinvestment in GP teaching persists at a time when teaching is expected to increase. Both aspects need to be addressed to facilitate high-quality undergraduate GP teaching and promotion of the expert medical generalist role.

BACKGROUND: Time in general practice offers medical students opportunities to learn a breadth of clinical knowledge and skills relevant to their future clinical practice. Undergraduate experiences shape career decisions and current recommendations are that 25% of undergraduate curriculum time should be focused on general practice. However, previous work demonstrated that GP teaching had plateaued or reduced in UK medical schools. Therefore, an up-to-date description of undergraduate GP teaching is timely. AIM: To describe the current picture of UK undergraduate GP teaching, including the amount of time and resources allocated to GP teaching. DESIGN AND SETTING: A cross-sectional questionnaire study across 36 UK medical schools. METHOD: The questionnaire was designed based on a previous survey performed in 2011–2013, with additional questions on human and financial support allocated to GP teaching. The questionnaire was piloted and revised prior to distribution to leads of undergraduate GP teaching in UK medical schools. RESULTS: The questionnaire response rate was 100%. GP teaching constituted an average of 9.2% of medical curricula; this was lower than previous figures, though the actual number of GP sessions has remained static. The majority (n = 23) describe plans to increase GP teaching in their local curricula over the next 5 years. UK-wide average payment was 55.60 GBP/student/session of in-practice teaching, falling well below estimated costs to practices. Allocation of human resources was varied. CONCLUSION: Undergraduate GP teaching provision has plateaued since 2000 and falls short of national recommendations. Chronic underinvestment in GP teaching persists at a time when teaching is expected to increase. Both aspects need to be addressed to facilitate high-quality undergraduate GP teaching and promotion of the expert medical generalist role.

Objective Copy number variation (CNV) has been associated with idiopathic short stature, small for gestational age and Silver-Russell syndrome (SRS). It has not been extensively investigated in growth hormone insensitivity (GHI; short stature, IGF-1 deficiency and normal/high GH) or previously in IGF-1 insensitivity (short stature, high/normal GH and IGF-1). Design and methods Array comparative genomic hybridisation was performed with ~60 000 probe oligonucleotide array in GHI (n = 53) and IGF-1 insensitivity (n = 10) subjects. Published literature, mouse models, DECIPHER CNV tracks, growth associated GWAS loci and pathway enrichment analyses were used to identify key biological pathways/novel candidate growth genes within the CNV regions. Results Both cohorts were enriched for class 3–5 CNVs (7/53 (13%) GHI and 3/10 (30%) IGF-1 insensitivity patients). Interestingly, 6/10 (60%) CNV subjects had diagnostic/associated clinical features of SRS. 5/10 subjects (50%) had CNVs previously reported in suspected SRS: 1q21 (n = 2), 12q14 (n = 1) deletions and Xp22 (n = 1), Xq26 (n = 1) duplications. A novel 15q11 deletion, previously associated with growth failure but not SRS/GHI was identified. Bioinformatic analysis identified 45 novel candidate growth genes, 15 being associated with growth in GWAS. The WNT canonical pathway was enriched in the GHI cohort and CLOCK was identified as an upstream regulator in the IGF-1 insensitivity cohorts. Conclusions Our cohort was enriched for low frequency CNVs. Our study emphasises the importance of CNV testing in GHI and IGF-1 insensitivity patients, particularly GHI subjects with SRS features. Functional experimental evidence is now required to validate the novel candidate growth genes, interactions and biological pathways identified.

In November 2016, the Medical Schools Council and Health Education England published a joint report chaired by Professor Val Wass: ‘By choice – not by chance’ to raise the profile of general practice as a positive career choice for medical students.\ud \ud We sought to evaluate the impact of the report by firstly, asking the views of Heads of GP teaching at UK medical schools whether and how the report has supported them in raising the profile of general practice and secondly, describing the initiatives developed by medical schools in a national survey. There was a perception reported by heads of GP teaching that the report has been highly influential in facilitating the promotion of general practice as a career to medical students. We describe multiple specific initiatives developed in response to the report’s recommendations. The national survey confirmed that whilst there is significant variation across medical schools in their response to the specific recommendations in the report, definite progress is being made. A number of areas that need particular consideration have been highlighted and we would recommend that future surveys are completed at appropriate time intervals to review further progress.

Background: We report (this meeting) somatic mutation of GNA11/Q in CTNNB1-mutant APAs. The recurrent co-driver mutation causes reversible hypertension in puberty, pregnancy, or menopause. We have investigated the molecular mechanism of this association. Methods: Gene expression profiles in 3 double mutant APAs were studied by unsupervised hierarchical clustering analysis and enrichment analysis of 362 differentially expressed genes and validated by qPCR, IFC and IHC in 10 double mutant APAs or transfected primary adrenal cells. Multiple region biopsies were performed in 7 adrenals adjacent to double-mutant APAs and 4 APAs with KCNJ5 or CACNA1D mutations. The findings of APA mutations in adjacent adrenals were replicated in each case by ddPCR ± NGS. Results: Unsupervised hierarchical clustering analysis showed clustering of the double-mutant APAs, and a high proportion of genes were many-fold upregulated compared to other APAs. LHCGR, TMEM132E, DKK1, C9orf84, FAP, GNRHR and MPP3 are among the genes with high expression. A small number of genes are down-regulated in the double-mutant APAs, including CYP11B1. qPCR confirmed an average of ~10 to 1000-fold higher expression of the hallmark genes in double-mutants. Enrichment analysis showed significant enrichment of features or terms concerned with cell junction and cell adhesion (P

Summary The results of a follow-up study of 200 males committed wader the MARA Act have been compared with general findings of other such studies. It was found that, if relapse is defined as any re-use of narcotics, the observed relapse rate of 87 per cent is equivalent to the 80–90 per cent relapse rates reported in other studies. Variables which have been related to relapse in other studies were also examined in this project. Some support was found for Wirdek's “maturation hypothesis”. Although no relationship was found between length of addiction and relapse, age was found to be related to relapse. Specifically, it was found that patients under 30 years of age used narcotics regularly or became readdicted at much higher rates than those over 30. Similarly, the rates of total abstinence or occasional use of narcotics were higher for those over 30. These findings indicate that Winick's hypothesis cannot be completely rejected. Employment was also found to be related to relapse in that those who found jobs relapsed less often than those unable to obtain employment. Most of the problems patients encountered in seeking a job seemed to be related more to their own personality problems than to other factors. Two other variables, ethnicity and education, were generally unrelated to relapse. Both the counselors and patients cited three general factors which led to relapse. One factor was use of narcotics to alleviate interpersonal stress. The second factor was the patient's craving or enjoyment of the euphoric effects and the “magnetic” pull of the addict subculture. Inability to cope with his own problems and frustration constituted the third general factor which helped to explain the relapse phenomenon. In citing reasons for abstinence, counselors and patients agreed that the patient's desire to stay clean, effectiveness of therapy, emotional support of the family and fear of the consequences of continued involvement in the drag subculture were the mast important factors in a patient remaining drug free. Further analysis of the stated reasons for abstinence indicated that little support was found for Winick's hypothesis that addicts “burn out”.