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The following report describes the clinical journey of a 5-month-old male infant who presented with a significant kidney injury following a diarrhoeal illness. His course was complicated by severe hypertension and a number of acute life-threatening events necessitating periods of time on the intensive care unit, where he received ventilatory support and underwent renal replacement therapy and treatment with a monoclonal antibody therapy. We take the reader on a stepwise journey from presentation through to final diagnosis, discussing important biochemical, haematological and radiological features where learning points are discussed. Guidance on the use of genomic testing strategies for the non-geneticist is provided in some detail with a particular focus on the trio exome analysis that identified the diagnosis for this young boy. This complex case not only provides a number of excellent learning opportunities but also highlights the importance of early involvement of the clinical genetics team and the relevance of the trio exome analysis for rapid identification of rare monogenic diseases. [ABSTRACT FROM AUTHOR]

The article discusses the epidemiology of Pierre Robin sequence (PRS) in the UK and Ireland, focusing on geographical variation in prevalence. PRS is a rare congenital malformation characterized by micrognathia, glossoptosis, and upper airway obstruction. The prevalence of PRS is estimated to be higher than previously reported, with significant geographical variation, being lowest in England and Wales, higher in Ireland, and highest in Scotland. The variation in prevalence may be due to factors such as misdiagnosis, inconsistent diagnostic criteria, and incomplete datasets. The article emphasizes the need for robust epidemiological studies, including comparative and spatial epidemiological studies, to better understand the cause and geographical variation of PRS. Genomic testing is also highlighted as essential for distinguishing between different types of PRS and identifying population genetic factors. Ultimately, this information is crucial for improving the recognition, management, and healthcare services for PRS patients in the UK and Ireland. [Extracted from the article]

Background: Therapeutic trials are now underway in genetic forms of frontotemporal dementia (FTD) but clinical outcome measures are limited. The two most commonly used measures, the Clinical Dementia Rating (CDR)+National Alzheimer's Disease Coordinating Center (NACC) Frontotemporal Lobar Degeneration (FTLD) and the FTD Rating Scale (FRS), have yet to be compared in detail in the genetic forms of FTD.Methods: The CDR+NACC FTLD and FRS were assessed cross-sectionally in 725 consecutively recruited participants from the Genetic FTD Initiative: 457 mutation carriers (77 microtubule-associated protein tau (MAPT), 187 GRN, 193 C9orf72) and 268 family members without mutations (non-carrier control group). 231 mutation carriers (51 MAPT, 92 GRN, 88 C9orf72) and 145 non-carriers had available longitudinal data at a follow-up time point.Results: Cross-sectionally, the mean FRS score was lower in all genetic groups compared with controls: GRN mutation carriers mean 83.4 (SD 27.0), MAPT mutation carriers 78.2 (28.8), C9orf72 mutation carriers 71.0 (34.0), controls 96.2 (7.7), p<0.001 for all comparisons, while the mean CDR+NACC FTLD Sum of Boxes was significantly higher in all genetic groups: GRN mutation carriers mean 2.6 (5.2), MAPT mutation carriers 3.2 (5.6), C9orf72 mutation carriers 4.2 (6.2), controls 0.2 (0.6), p<0.001 for all comparisons. Mean FRS score decreased and CDR+NACC FTLD Sum of Boxes increased with increasing disease severity within each individual genetic group. FRS and CDR+NACC FTLD Sum of Boxes scores were strongly negatively correlated across all mutation carriers (rs=-0.77, p<0.001) and within each genetic group (rs=-0.67 to -0.81, p<0.001 in each group). Nonetheless, discrepancies in disease staging were seen between the scales, and with each scale and clinician-judged symptomatic status. Longitudinally, annualised change in both FRS and CDR+NACC FTLD Sum of Boxes scores initially increased with disease severity level before decreasing in those with the most severe disease: controls -0.1 (6.0) for FRS, -0.1 (0.4) for CDR+NACC FTLD Sum of Boxes, asymptomatic mutation carriers -0.5 (8.2), 0.2 (0.9), prodromal disease -2.3 (9.9), 0.6 (2.7), mild disease -10.2 (18.6), 3.0 (4.1), moderate disease -9.6 (16.6), 4.4 (4.0), severe disease -2.7 (8.3), 1.7 (3.3). Sample sizes were calculated for a trial of prodromal mutation carriers: over 180 participants per arm would be needed to detect a moderate sized effect (30%) for both outcome measures, with sample sizes lower for the FRS.Conclusions: Both the FRS and CDR+NACC FTLD measure disease severity in genetic FTD mutation carriers throughout the timeline of their disease, although the FRS may be preferable as an outcome measure. However, neither address a number of key symptoms in the FTD spectrum, for example, motor and neuropsychiatric deficits, which future scales will need to incorporate. [ABSTRACT FROM AUTHOR]

Objectives: To determine whether the familial clustering of amyotrophic lateral sclerosis (ALS) cases and the phenotype of the disease may help identify the pathogenic genes involved.Methods: We conducted a targeted next-generation sequencing analysis on 235 French familial ALS (FALS), unrelated probands to identify mutations in 30 genes linked to the disease. The genealogy, that is, number of cases and generations with ALS, gender, age, site of onset and the duration of the disease were analysed.Results: Regarding the number of generations, 49 pedigrees had only one affected generation, 152 had two affected generations and 34 had at least three affected generations. Among the 149 pedigrees (63.4%) for which a deleterious variant was found, an abnormal G4C2 expansion in C9orf72 was found in 98 cases as well as SOD1, TARBP or FUS mutations in 30, 9 and 7 cases, respectively. Considering pedigrees from the number of generations, abnormal G4C2 expansion in C9orf72 was more frequent in pedigrees with pairs of affected ALS cases, which represented 65.2% of our cohort. SOD1 mutation involved all types of pedigrees. No TARDBP nor FUS mutation was present in monogenerational pedigrees. TARDBP mutation predominated in bigenerational pedigrees with at least three cases and FUS mutation in multigenerational pedigrees with more than seven cases, on average, and with an age of onset younger than 45 years.Conclusion: Our results suggest that familial clustering, phenotypes and genotypes are interconnected in FALS, and thus it might be possible to target the genetic screening from the familial architecture and the phenotype of ALS cases. [ABSTRACT FROM AUTHOR]

Objective: To understand how to maximise recruitment of young infants with Down's syndrome (DS) into research through qualitative interviews with parents and care providers. In complex neonatal and genetic conditions such as DS, frequently diagnosed after birth, parents may go through a period of adaptation. These factors need consideration when overcoming barriers to recruitment.Participants and Design: Participants, who were drawn from health professionals and volunteers working with families experiencing DS, were recruited using a purposive sampling strategy. Semistructured telephone interviews were completed with nine paediatricians, three research nurses and six family support workers. Five of those interviewed had a child with DS. The interviews were transcribed and analysed thematically.Results: A positive decision to take part in a 'from-birth' cohort study depends on factors such as the child's overall health, parent demographics (educational background and ethnicity), medical interactions that take place with the families (communication) and study logistics. The data suggest that recruitment methods need to take all these factors into consideration. Multiple recruitment methods should be considered including face to face, through parent and support groups, websites and social media. There also needs to be flexibility in the research timings to fit around the needs of the child and parents.Conclusion: Researchers need to be aware of the variable responses elicited by families to a diagnosis of DS for their baby and be sensitive to the child's current medical status. This does not preclude recruitment into studies, but to maximise uptake good communication and flexibility is essential. [ABSTRACT FROM AUTHOR]

Objectives: Impulse control disorders (ICD) are commonly associated with dopamine replacement therapy (DRT) in patients with Parkinson's disease (PD). Our aims were to estimate ICD heritability and to predict ICD by a candidate genetic multivariable panel in patients with PD.Methods: Data from de novo patients with PD, drug-naïve and free of ICD behaviour at baseline, were obtained from the Parkinson's Progression Markers Initiative cohort. Incident ICD behaviour was defined as positive score on the Questionnaire for Impulsive-Compulsive Disorders in PD. ICD heritability was estimated by restricted maximum likelihood analysis on whole exome sequencing data. 13 candidate variants were selected from the DRD2, DRD3, DAT1, COMT, DDC, GRIN2B, ADRA2C, SERT, TPH2, HTR2A, OPRK1 and OPRM1 genes. ICD prediction was evaluated by the area under the curve (AUC) of receiver operating characteristic (ROC) curves.Results: Among 276 patients with PD included in the analysis, 86% started DRT, 40% were on dopamine agonists (DA), 19% reported incident ICD behaviour during follow-up. We found heritability of this symptom to be 57%. Adding genotypes from the 13 candidate variants significantly increased ICD predictability (AUC=76%, 95% CI (70% to 83%)) compared to prediction based on clinical variables only (AUC=65%, 95% CI (58% to 73%), p=0.002). The clinical-genetic prediction model reached highest accuracy in patients initiating DA therapy (AUC=87%, 95% CI (80% to 93%)). OPRK1, HTR2A and DDC genotypes were the strongest genetic predictive factors.Conclusions: Our results show that adding a candidate genetic panel increases ICD predictability, suggesting potential for developing clinical-genetic models to identify patients with PD at increased risk of ICD development and guide DRT management. [ABSTRACT FROM AUTHOR]

Gain-of-function mutations in JAK2 are the molecular hallmarks of polycythaemia vera (PV), one of the myeloproliferative neoplasms. Most (~95%) patients harbour V617F mutation in exon 15, while the rest have small insertion/deletion mutations in exon 12. We investigated JAK2 mutations in 42 Korean patients with PV. V617F was detected by sequencing and allele-specific PCR. When V617F was negative, sequencing and fragment length analyses were performed to detect exon 12 mutations. As a result, all patients had JAK2 mutations: 37 (88%) harboured V617F, and 5 (12%) had exon 12 mutations. Two patients had novel exon 12 mutations (H538_R541delinsLII and F537_K539delinsVL). Genotype-phenotype correlations demonstrated lower white blood cell and platelet counts in exon 12 mutations than V617F. The frequency of JAK2 exon 12 mutations was higher than expected in Korean patients with PV. Molecular genetic testing for JAK2 exon 12 mutations is mandatory for diagnosis and genotype-phenotype correlations in patients with erythrocytosis and suspected PV. [ABSTRACT FROM AUTHOR]

In genetic medicine, a patient's diagnosis can mean their family members are also at risk, raising a question about how consent and confidentiality should function in clinical genetics. This question is particularly pressing when it is unclear whether a patient has shared information. Conventionally, healthcare professionals view confidentiality at an individual level and 'disclosure without consent' as the exception, not the rule. The relational joint account model, by contrast, conceptualises genetic information as confidential at the familial level and encourages professionals to take disclosure as the default position. In this study, we interviewed 33 patients about consent and confidentiality and analysed data thematically. Our first theme showed that although participants thought of certain aspects of genetic conditions--for example, the way they affect day-to-day health--as somewhat personal, they perceived genetic information--for example, the mutation in isolation--as familial. Most thought these elements were separable and thought family members had a right to know the latter, identifying a broad range of harms that would justify disclosure. Our second theme illustrated that participants nonetheless had some concerns about what, if any, implications there would be of professionals treating such information as familial and they emphasised the importance of being informed about the way their information would be shared. Based on these results, we recommend that professionals take disclosure as the default position, but make clear that they will treat genetic information as familial during initial consultations and address any concerns therein. [ABSTRACT FROM AUTHOR]

CRISPR-Cas9 (clustered regularly interspaced short palindromic repeats-CRISPR associated nuclease 9) systems have emerged as versatile and convenient (epi) genome editing tools and have become an important player in medical genetic research. CRISPR-Cas9 and its variants such as catalytically inactivated Cas9 (dead Cas9, dCas9) and scaffold-incorporating single guide sgRNA (scRNA) have been applied in various genomic screen studies. CRISPR screens enable high-throughput interrogation of gene functions in health and diseases. Compared with conventional RNAi screens, CRISPR screens incur less off-target effects and are more versatile in that they can be used in multiple formats such as knockout, knockdown and activation screens, and can target coding and non-coding regions throughout the genome. This powerful screen platform holds the potential of revolutionising functional genomic studies in the near future. Herein, we introduce the mechanisms of (epi)genome editing mediated by CRISPR-Cas9 and its variants, introduce the procedures and applications of CRISPR screen in functional genomics, compare it with conventional screen tools and at last discuss current challenges and opportunities and propose future directions. [ABSTRACT FROM AUTHOR]

Background Mantle cell lymphoma (MCL) is an aggressive disease with genetic heterogeneity and discrete clinical subtypes. MCL is rarely CD10 positive. These cases raise the question whether a subset of MCL may be germinal centre (GC) derived, and have distinct clinicopathological characteristics. Aims and methods A series of nine CD10-positive MCL cases is described herein. The clinicopathological and immunophenotypic features, immunoglobulin somatic hypermutation (SHM) status and gene expression profile (GEP) data are detailed. These features were compared with two independent sets (n=20, each) of CD10-negative MCL cases (controls), which were randomly selected from our institutional registry. Results GEP showed distinct expression of a GC signature in CD10-positive MCL cases with minimal impact on downstream signalling pathways. There were no significant differences in the clinicopathological features or clinical outcome between our CD10-positive and CD10-negative MCL cases. The frequency of SHM was comparable with established data. Conclusions This study provides convincing evidence that CD10 expression is related to a distinct GC signature in MCL cases, but without clinical or biological implications. [ABSTRACT FROM AUTHOR]

MicroRNAs (miRNAs) are small, non-coding, RNA molecules approximately 22 nucleotides in length which act as post-transcriptional regulators of gene expression. Individual miRNAs have been shown to regulate the expression of multiple genes. Conversely, the expression of individual genes can be regulated by multiple miRNAs. Consequently, since their discovery just over 20 years ago, miRNAs have been identified as key regulators of complex biological processes linked to multiple cardiovascular pathologies, including left ventricular hypertrophy, ischaemic heart disease, heart failure, hypertension and arrhythmias. Furthermore, since the finding that miRNAs are present in the circulation, they have been investigated as novel biomarkers, especially in the context of acute myocardial infarction (AMI) and heart failure. While there is little convincing evidence that miRNAs can outperform traditional biomarkers, such as cardiac troponins, in the diagnosis of AMI, there is potential for miRNAs to complement existing risk prediction models and act as valuable markers of post-AMI prognosis. Encouragingly, the concept of miRNA-based therapeutics is developing, with synthetic antagonists of miRNAs (antagomiRs) currently in phase II trials for the treatment of chronic hepatitis C virus infection. In the cardiovascular field, promising preclinical studies suggest that they could be useful in treating disorders ranging from heart failure to dyslipidaemia, although several challenges related to specificity and targeted delivery remain to be overcome. Through this review, we provide clinicians with a brief overview of the ever-expanding world of miRNAs. [ABSTRACT FROM AUTHOR]

Background Whole-genome sequencing (WGS) and whole-exome sequencing (WES) technologies are increasingly used to identify disease-contributing mutations in human genomic studies. It can be a significant challenge to process such data, especially when a large family or cohort is sequenced. Our objective was to develop a big data toolset to efficiently manipulate genome-wide variants, functional annotations and coverage, together with conducting family based sequencing data analysis. Methods Hadoop is a framework for reliable, scalable, distributed processing of large data sets using MapReduce programming models. Based on Hadoop and HBase, we developed SeqHBase, a big data-based toolset for analysing family based sequencing data to detect de novo, inherited homozygous, or compound heterozygous mutations that may contribute to disease manifestations. SeqHBase takes as input BAM files (for coverage at every site), variant call format (VCF) files (for variant calls) and functional annotations (for variant prioritisation). Results We applied SeqHBase to a 5-member nuclear family and a 10-member 3-generation family with WGS data, as well as a 4-member nuclear family with WES data. Analysis times were almost linearly scalable with number of data nodes. With 20 data nodes, SeqHBase took about 5 secs to analyse WES familial data and approximately 1 min to analyse WGS familial data. Conclusions These results demonstrate SeqHBase's high efficiency and scalability, which is necessary as WGS and WES are rapidly becoming standard methods to study the genetics of familial disorders. [ABSTRACT FROM AUTHOR]

Objectives Recently, several studies documented that de novo mutations (DNMs) play important roles in the aetiology of sporadic diseases. Next-generation sequencing (NGS) enables variant calling at single-base resolution on a genome-wide scale. However, accurate identification of DNMs from NGS data still remains a major challenge. We developed mirTrios, a web server, to accurately detect DNMs and rare inherited mutations from NGS data in sporadic diseases. Methods The expectation-maximisation (EM) model was adopted to accurately identify DNMs from variant call files of a trio generated by GATK (Genome Analysis Toolkit). The GATK results, which contain certain basic properties (such as PL, PRT and PART), are iteratively integrated into the EM model to strike a threshold for DNMs detection. Training sets of true and false positive DNMs in the EM model were built from whole genome sequencing data of 64 trios. Results With our in-house whole exome sequencing datasets from 20 trios, mirTrios totally identified 27 DNMs in the coding region, 25 of which (92.6%) are validated as true positives. In addition, to facilitate the interpretation of diverse mutations, mirTrios can also be employed in the identification of rare inherited mutations. Embedded with abundant annotation of DNMs and rare inherited mutations, mirTrios also supports known diagnostic variants and causative gene identification, as well as the prioritisation of novel and promising candidate genes. Conclusions mirTrios provides an intuitive interface for the general geneticist and clinician, and can be widely used for detection of DNMs and rare inherited mutations, and annotation in sporadic diseases. mirTrios is freely available at http://centre.bioinformatics.zj.cn/mirTrios/. [ABSTRACT FROM AUTHOR]

Aims Near-tetraploidy/tetraploidy (NT/T) is a rare cytogenetic alteration in acute myeloid leukaemia (AML). NT/T-AML is categorised as complex cytogenetics and therefore, presumed to have an unfavourable prognosis. Our aim is to further characterise the clinical, morphological, cytogenetic and prognostic features of NT/T-AML. Methods We searched our cytogenetic laboratory database from 1991 to 2012 to reveal 13 cases of NT/TAML. Each case was evaluated with regard to its demographics, morphology, immunophenotype and prognosis. Specific morphological features included blast size, irregularity of nuclear contours, cytoplasmic vacuoles, and presence and lineage of dysplasia. Results Eleven men and two women had a median age of 68 years. Blasts were predominately large (11/13). Eight of 13 patients had AML with myelodysplasia-related changes. Sixty-nine per cent of patients achieved complete remission (CR). Median overall survival (OS) was 8.6 months. CR rate and median OS in cases with ≥5 cytogenetic abnormalities were 71% and 6 months, compared with 67% and 18.1 months in cases with <5 abnormalities. Conclusions NT/T-AML occurs in older males, exhibits large blast size and is associated with myelodysplasia. Unlike previously reported data, our study reveals an overall better prognosis in this older population with NT/ T-AML than was expected for a complex karyotype AML. Cytogenetic complexity independent of ploidy status did not greatly affect the high CR rates, but did appear to be a better estimation of prognostic risk in terms of median OS. [ABSTRACT FROM AUTHOR]

Aims Assessing whether next-generation DNA sequencing (NGS) can be used to screen prostate cancer for multiple gene alterations in men routinely diagnosed with this disease and/or who are entered into clinical trials. Previous studies are limited and have reported only low success rates. Methods We marked areas of cancer on H&E-stained sections from formalin-fixed needle biopsies, and used these as templates to dissect cancer-rich tissue from adjacent unstained sections. DNA was prepared using a Qiagen protocol modified to maximise DNA yield. The DNA was screened simultaneously for mutations in 365 cancer-related genes using an Illumina HiSeq 2000 NGS platform. Results From 63 prostate cancers examined, 59 (94%) of the samples yielded at least 30 ng of DNA, the minimum amount of DNA considered suitable for NGS analysis. Patients in the D'Amico high-risk group yielded an average of 1033 ng, intermediate-risk patients 401 ng, and low-risk patients 97 ng. NGS of eight samples selected from high-risk and intermediate-risk groups gave a median exon read depth of 962 and detected TMPRRS2-ERG fusions, as well as a variety of mutations including those in the SPOP, TP53, ATM, MEN1, NBPF10, NCOR2, PIK3CB and MAP2K5 (MEK5) genes. Conclusions Using the methods presented here, NGS technologies can be used to screen a high proportion of patients with prostate cancer for mutations in cancerrelated genes in tissue samples opening up its general use in the context of clinical trials or routine diagnosis. [ABSTRACT FROM AUTHOR]

Purpose To validate three models for predicting proliferative vitreoretinopathy (PVR) based on the analysis of genotypic data and relevant clinical characteristics. Methods The validation series consisted of data from 546 patients operated on from primary rhegmatogenous retinal detachment (RRD) coming from centres in the Netherlands, Portugal, Spain and the UK. Temporal and geographical validation was performed. The discrimination capability of each model was analysed and compared with the original series, using a receiver operating curve. Then, clinical variables were combined in order to improve the predictive capability. A risk reclassification analysis was performed with and without each one of the variables. Reclassification of patients was compared and models were readjusted in the original series. Readjusted models were further validated. Results One of the models showed good predictability in the temporal sample as well as in the original series (area under the curve (AUC) original=0.7352; AUC temporal=0.6457, 95% CI 50.17 to 78.97). When clinical variables were included, only pre-existent PVR improves the predictability of this model in the validation series (temporal and geographical samples) (AUC original=0.7940 vs AUC temporal=0.7744 and AUC geographical=0.7152). The other models showed acceptable AUC values when clinical variables were included although they were less accurate than in the original series. Conclusions Genetic profiling of patients with RRD can improve the predictability of PVR in addition to the wellknown clinical biomarkers. This validated formula could be a new tool in our current clinical practice in order to identify those patients at high risk of developing PVR. [ABSTRACT FROM AUTHOR]

This paper engages with the question of what it is to 'do good medical ethics' in two ways. It begins with an exploration of what it might mean to say that health professionals practise good medical ethics as part of practising good ethical medicine. Using the example of the Genethics Club, a well-established national ethics forum for genetics professionals in the UK, the paper develops an account of moral craftsmanship grounded in the concepts of shared moral commitments and practices, moral work, ethics and living morality. In the light of this discussion, the paper goes on to consider what it might mean for a specialist in medical ethics, a bioethicist, to do good medical ethics. Finally, a research agenda focusing on the challenges of thinking about good medical ethics in a global context and a proposal for an innovative approach to bioethics methodology is outlined. [ABSTRACT FROM AUTHOR]

Background: Genetic variants within genes involved in fibrillogenesis have previously been implicated in anterior cruciate ligament (ACL) injury susceptibility. Proteoglycans also have important functions in fibrillogenesis and maintaining the structural integrity of ligaments. Genes encoding proteoglycans are plausible candidates to be investigated for associations with ACL injury susceptibility; polymorphisms within genes encoding the proteoglycans aggrecan (ACAN), biglycan (BGN), decorin (DCN), fibromodulin (FMOD) and lumican (LUM) were examined. Methods: A case–control genetic association study was conducted. 227 participants with surgically diagnosed ACL ruptures (ACL group) and 234 controls without any history of ACL injury were genotyped for 10 polymorphisms in 5 proteoglycan genes. Inferred haplotypes were constructed for specific regions. Results: The G allele of ACAN rs1516797 was significantly under-represented in the controls ( p=0.024; OR=0.72; 95% CI 0.55 to 0.96) compared with the ACL group. For DCN rs516115, the GG genotype was significantly over-represented in female controls (p=0.015; OR=9.231; 95%CI 1.16 to 73.01) compared with the ACL group and the AA genotype was significantly under-represented in controls (p=0.013; OR=0.33; 95% CI 0.14 to 0.78) compared with the female non-contact ACL injury subgroup. Haplotype analyses implicated regions overlapping ACAN (rs2351491 C>T-rs1042631 T>C-rs1516797 T>G), BGN (rs1126499 C>T-rs1042103 G>A) and LUM-DCN (rs2268578 T>C-rs13312816 A>T-rs516115 A>G) in ACL injury susceptibility. Conclusions: These independent associations and haplotype analyses suggest that regions within ACAN, BGN, DCN and a region spanning LUM–DCN are associated with ACL injury susceptibility. Taking into account the functions of these genes, it is reasonable to propose that genetic sequence variability within the genes encoding proteoglycans may potentially modulate the ligament fibril properties. [ABSTRACT FROM AUTHOR]

Background De novo mutations are emerging as an important cause of neurocognitive impairment, and whole exome sequencing of case-parent trios is a powerful way of detecting them. Here, we report the findings in four such trios. Methods The Deciphering Developmental Disorders study is using whole exome sequencing in family trios to investigate children with severe, sporadic, undiagnosed developmental delay. Three of our patients were ascertained from the first 1133 children to have been investigated through this large-scale study. Case 4 was a phenotypically isolated case recruited into an undiagnosed rare disorders sequencing study. Results Protein-altering de novo mutations in PURA were identified in four subjects. They include two different frameshifts, one inframe deletion and one missense mutation. PURA encodes Pur-α, a highly conserved multifunctional protein that has an important role in normal postnatal brain development in animal models. The associated human phenotype of de novo heterozygous mutations in this gene is variable, but moderate to severe neurodevelopmental delay and learning disability are common to all. Neonatal hypotonia, early feeding difficulties and seizures, or 'seizure-like' movements, were also common. Additionally, it is suspected that anterior pituitary dysregulation may be within the spectrum of this disorder. Psychomotor developmental outcomes appear variable between patients, and we propose a possible genotype-phenotype correlation, with disruption of Pur repeat III resulting in a more severe phenotype. Conclusions These findings provide definitive evidence for the role of PURA in causing a variable syndrome of neurodevelopmental delay, learning disability, neonatal hypotonia, feeding difficulties, abnormal movements and epilepsy in humans, and help clarify the role of PURA in the previously described 5q31.3 microdeletion phenotype. [ABSTRACT FROM AUTHOR]