Clinical findings and a DNA methylation signature in kindreds with alterations in ZNF711.

ZNF711 is one of eleven zinc-finger genes on the X chromosome that have been associated with X-linked intellectual disability. This association is confirmed by the clinical findings in 20 new cases in addition to 11 cases previously reported. No consistent growth aberrations, craniofacial dysmorphology, malformations or neurologic findings are associated with alterations in ZNF711. The intellectual disability is typically mild and coexisting autism occurs in half of the cases. Carrier females show no manifestations. A ZNF711-specific methylation signature has been identified which can assist in identifying new cases and in confirming the pathogenicity of variants in the gene.

Qualitative Olfactory Disorders: Patient Experiences and Self-Management.

BACKGROUND: Qualitative olfactory disorders in the form of parosmia and phantosmia are very subjective and cannot be measured at present. They pose an unpleasant experience for patients and a therapeutic challenge for clinicians. OBJECTIVE: This study aimed to characterise the specific experiences of patients affected by the qualitative symptoms of parosmia and phantosmia including both triggers for symptoms and self-help measures they have tried. METHODS: A cross-sectional survey questionnaire was developed with the input of patient experts within the charity Fifth Sense. The survey was then open online for 3 months to charity members complaining of qualitative symptoms. The survey captured the frequency and impact of symptoms and self-management undertaken. Reflective feedback was also captured from a patient workshop. RESULTS: There were 100 participants; 61% female, age range 13-88. Common self-reported aetiology included sinonasal disease (17%), idiopathic (33%) and post-viral olfactory loss (26%) and post-traumatic olfactory loss (23%). Parosmia was reported as a daily symptom in 67% compared to 31% for phantosmia; 36% complained of suffering with both symptoms. Only 4% of respondents reported having received any successful treatment for their qualitative symptoms and 58% reported having received no treatment whatsoever. Olfactory training was the most common self-management method reported. CONCLUSION: This study illustrates that qualitative disturbances remain problematic for those who experience them due to the duration of symptoms, the relative lack of experience or knowledge amongst medical professionals and the lack of therapeutic options. In future, consideration needs to be given to adaptation and coping strategies to help patients deal with these symptoms.

Barriers to effective health care for patients who have smell or taste disorders.

OBJECTIVES: Smell/taste disturbances are a common but underrated, under-researched and under treated sensory loss and an independent risk factor for reduced longevity. This study aimed to characterise the experience of patients with these disorders in seeking help. DESIGN: The study was designed by patients together with clinicians through a dedicated workshop and conducted as a cross-sectional survey to capture experiences in public and private healthcare settings internationally. SETTING: Primary, secondary and tertiary care. PARTICIPANTS: Any members of the public self-reporting a smell/taste disorder were invited to participate. MAIN OUTCOME MEASURES: The survey captured information including experience of getting consultations and referrals to medical professionals, treatments offered, costs incurred and related problems with mental health. RESULTS: Of 673 participants; 510 female, 160 male, three not stated, self-reported aetiology included sinonasal disease (24%), idiopathic (24%) and post-viral olfactory dysfunction (22%); true gustatory disorders were typically rare. Failure of medical professionals to recognise the problem was a key concern - 64%, 76% and 47% of GPs, ENT specialists and Neurologists acknowledged, respectively. Other issues included repeated ineffective treatments, difficulties getting referrals to secondary/tertiary care, mental health problems (60%) and a mean personal cost of £421 to seeking advice and treatment. Whilst the participants were self-selecting, however, they do represent those who are seeking help and intervention for their disorders. CONCLUSION: There is an unmet need for these patients in accessing health care including a clear need to improve education of and engagement with the medical profession in Otorhinolaryngology, General Practice and other specialties, in order to remove the current barriers they face.

Constraint and conservation of paired-type homeodomains predicts the clinical outcome of missense variants of uncertain significance.

The need to interpret the pathogenicity of novel missense variants of unknown significance identified in the homeodomain of X-chromosome aristaless-related homeobox (ARX) gene prompted us to assess the utility of conservation and constraint across these domains in multiple genes compared to conventional in vitro functional analysis. Pathogenic missense variants clustered in the homeodomain of ARX contribute to intellectual disability (ID) and epilepsy, with and without brain malformation in affected males. Here we report novel c.1112G>A, p.Arg371Gln and c.1150C>T, p.Arg384Cys variants in male patients with ID and severe seizures. The third case of a male patient with a c.1109C>T, p.Ala370Val variant is perhaps the first example of ID and autism spectrum disorder (ASD), without seizures or brain malformation. We compiled data sets of pathogenic variants from ClinVar and presumed benign variation from gnomAD and demonstrated that the high levels of sequence conservation and constraint of benign variation within the homeodomain impacts upon the ability of publicly available in silico prediction tools to accurately discern likely benign from likely pathogenic variants in these data sets. Despite this, considering the inheritance patterns of the genes and disease variants with the conservation and constraint of disease variants affecting the homeodomain in conjunction with current clinical assessments may assist in predicting the pathogenicity of missense variants, particularly for genes with autosomal recessive and X-linked patterns of disease inheritance, such as ARX. In vitro functional analysis demonstrates that the transcriptional activity of all three variants was diminished compared to ARX-Wt. We review the associated phenotypes of the published cases of patients with ARX homeodomain variants and propose expansion of the ARX-related phenotype to include severe ID and ASD without brain malformations or seizures. We propose that the use of the constraint and conservation data in conjunction with consideration of the patient phenotype and inheritance pattern may negate the need for the experimental functional validation currently required to achieve a diagnosis.

STAC3 variants cause a congenital myopathy with distinctive dysmorphic features and malignant hyperthermia susceptibility.

SH3 and cysteine-rich domain-containing protein 3 (STAC3) is an essential component of the skeletal muscle excitation-contraction coupling (ECC) machinery, though its role and function are not yet completely understood. Here, we report 18 patients carrying a homozygous p.(Trp284Ser) STAC3 variant in addition to a patient compound heterozygous for the p.(Trp284Ser) and a novel splice site change (c.997-1G > T). Clinical severity ranged from prenatal onset with severe features at birth, to a milder and slowly progressive congenital myopathy phenotype. A malignant hyperthermia (MH)-like reaction had occurred in several patients. The functional analysis demonstrated impaired ECC. In particular, KCl-induced membrane depolarization resulted in significantly reduced sarcoplasmic reticulum Ca2+ release. Co-immunoprecipitation of STAC3 with CaV 1.1 in patients and control muscle samples showed that the protein interaction between STAC3 and CaV 1.1 was not significantly affected by the STAC3 variants. This study demonstrates that STAC3 gene analysis should be included in the diagnostic work up of patients of any ethnicity presenting with congenital myopathy, in particular if a history of MH-like episodes is reported. While the precise pathomechanism remains to be elucidated, our functional characterization of STAC3 variants revealed that defective ECC is not a result of CaV 1.1 sarcolemma mislocalization or impaired STAC3-CaV 1.1 interaction.

Successful pregnancies and reduced treatment requirement while breast feeding in a patient with congenital hypoparathyroidism due to homozygous c.68C>A null parathyroid hormone gene mutation.

A female patient with consanguineous parents presented at the age of 4 with isolated hypoparathyroidism due to a parathyroid hormone (PTH) gene mutation. She was managed with alfacalcidol and calcium supplements, and developed normally. Her consanguineous parents described symptoms suggestive of hypocalcaemia but had normal serum calcium and low normal PTH levels. A molecular diagnosis obtained in her adulthood revealed the presence of homozygous point mutation (c.68C>A) in exon 2 introducing a premature stop codon resulting in a non-functional precursor protein. This mutation has been reported only once before. Our patient remained on stable doses of alfacalcidol during pregnancy, but stopped all supplementation while breast feeding. This case confirms that alternative mechanisms (likely breast-derived parathyroid hormone-related protein) contribute to calcium homeostasis during breast feeding. Heterozygotes for the c.68C>A mutation may have latent hypoparathyroidism and maintain calcium homeostasis except during prolonged hypocalcaemia. This would suggest incomplete dominance, or a dose effect of the wild-type PTH allele.

A retrospective audit of the characteristics and treatment outcomes in patients with diabetes-related charcot neuropathic osteoarthropathy.

AIMS: To review the characteristics, management and outcomes one year after diagnosis in patients with diabetes related charcot neuropathic osteoarthropathy (CN) treated at the Diabetes Podiatry service, Waitemata District Health Board (WDHB) between 2000-2014. METHODS: Patients with diabetes and recorded diagnosis of CN were identified from the podiatry service records. Clinical details were retrospectively obtained from WDHB databases and patient medical records. RESULTS: Forty-one patients were included, 31 had type 2 diabetes, 10 had type 1 diabetes. At presentation, the median duration of all-type diabetes was 15 years. The median time from symptom onset to diagnosis was 17 weeks. Symptoms at presentation were: oedema (49%), warmth (73%), erythema (17%), swelling (90%) and pain (60%). Concomitant ulcers were present in 32%, deformities 83%, osteomyelitis 2% and septic arthritis 2%. Mean time to ambulation in modified shoes was 21.3 weeks (±11.5). Complication rates one year from diagnosis for ulcers, osteomyelitis, amputations and all-cause mortality were 34%, 2%, 2% and 5% respectively. CONCLUSION: Time to diagnosis of CN was shorter than previously reported, though the high rate of deformities still suggests a significant delay in diagnosis. Increased education of healthcare professionals and people with diabetes-related neuropathy is important to ensure early diagnosis and appropriate management to reduce deformities and complications.

Management of Rabies Prophylaxis for Potential Bat Exposures in a Level III Neonatal Intensive Care Unit.

This report describes the unique challenges of managing potential exposure to bats in a neonatal intensive care unit. The outcome demonstrates that rabies post-exposure prophylaxis can be safely administered to preterm infants with evidence that preterm infants are able to develop adequate titers post vaccination. Infect Control Hosp Epidemiol 2017;38:483-485.

Mutations in CDC45, Encoding an Essential Component of the Pre-initiation Complex, Cause Meier-Gorlin Syndrome and Craniosynostosis.

DNA replication precisely duplicates the genome to ensure stable inheritance of genetic information. Impaired licensing of origins of replication during the G1 phase of the cell cycle has been implicated in Meier-Gorlin syndrome (MGS), a disorder defined by the triad of short stature, microtia, and a/hypoplastic patellae. Biallelic partial loss-of-function mutations in multiple components of the pre-replication complex (preRC; ORC1, ORC4, ORC6, CDT1, or CDC6) as well as de novo stabilizing mutations in the licensing inhibitor, GMNN, cause MGS. Here we report the identification of mutations in CDC45 in 15 affected individuals from 12 families with MGS and/or craniosynostosis. CDC45 encodes a component of both the pre-initiation (preIC) and CMG helicase complexes, required for initiation of DNA replication origin firing and ongoing DNA synthesis during S-phase itself, respectively, and hence is functionally distinct from previously identified MGS-associated genes. The phenotypes of affected individuals range from syndromic coronal craniosynostosis to severe growth restriction, fulfilling diagnostic criteria for Meier-Gorlin syndrome. All mutations identified were biallelic and included synonymous mutations altering splicing of physiological CDC45 transcripts, as well as amino acid substitutions expected to result in partial loss of function. Functionally, mutations reduce levels of full-length transcripts and protein in subject cells, consistent with partial loss of CDC45 function and a predicted limited rate of DNA replication and cell proliferation. Our findings therefore implicate the preIC as an additional protein complex involved in the etiology of MGS and connect the core cellular machinery of genome replication with growth, chondrogenesis, and cranial suture homeostasis.

An evaluation of the impact of memory and mood on antiepileptic drug adherence.

RATIONALE: Antiepileptic drugs are the mainstay of treatment for patients with epilepsy. Adherence to the prescribed regimen is a major factor in achieving a reduced seizure burden, which can decrease morbidity and mortality. Patients with epilepsy oftentimes complain about difficulty with memory. Because little is known about the relationship between memory and mood and adherence, the purpose of this project was to determine the impact of the confounding factors of memory and mood on antiepileptic drug adherence in patients with epilepsy. METHODS: One hundred adult patients with epilepsy were recruited from the outpatient neurology clinic for this cross-sectional study. Patients who met the inclusion criteria completed measures of subjective memory (subset of 6 memory questions from the QOLIE-89) and objective memory (Hopkins Verbal Learning Test - Revised), subjective adherence (Morisky scale) and objective adherence (medication possession ratio), and mood (Neurological Disorders Depression Inventory for Epilepsy). Refill records from each patient's community pharmacy were used to objectively assess adherence. Medication possession ratios were calculated based on the antiepileptic drug refill records over the previous 6months. Patients were considered adherent if their MPR was >80%. RESULTS: Women made up the majority of the sample (n=59), and, on average, patients had been living with epilepsy for nearly 20years. Approximately 40% of the sample were on antiepileptic drug monotherapy; most patients (>70%) took their antiepileptic drugs twice daily, and the mean number of total medications was 4.25±2.98. Based on the objective measure of adherence, 35% of the patients were nonadherent. Patients self-reported better adherence than what was objectively measured. Only the retention metric of the objective memory measure differentiated adherent patients from nonadherent patients. Patients in the adherent group had significantly lower depression scores (indicating better mood) compared with those in the nonadherent group (p=0.04). CONCLUSIONS: Objective memory measures were not robustly correlated with adherence. However, we observed that patients with higher depressed mood scores were more likely to be nonadherent. By targeting patients with epilepsy and comorbid depression, practitioners may identify patients at greatest risk of nonadherence and subsequent harm.

Delineation of the 3p14.1p13 microdeletion associated with syndromic distal limb contractures.

Distal limb contractures (DLC) represent a heterogeneous clinical and genetic condition. Overall, 20-25% of the DLC are caused by mutations in genes encoding the muscle contractile apparatus. Large interstitial deletions of the 3p have already been diagnosed by standard chromosomal analysis, but not associated with a specific phenotype. We report on four patients with syndromic DLC presenting with a de novo 3p14.1p13 microdeletion. The clinical features associated multiple contractures, feeding problems, developmental delay, and intellectual disability. Facial dysmorphism was constant with low-set posteriorly rotated ears and blepharophimosis. Review of previously reported cases with a precise mapping of the deletions, documented a 250 kb smallest region of overlap (SRO) necessary for DLC. This region contained one gene, EIF4E3, the first three exons of the FOXP1 gene, and an intronic enhancer of FOXP1 named hs1149. Sanger sequencing and locus quantification of hs1149, EIF4E3, and FOXP1 in a cohort of 11 French patients affected by DLC appeared normal. In conclusion, we delineate a new microdeletion syndrome involving the 3p14.1p13 locus and associated with DLC and severe developmental delay.

Mutations in NOTCH1 cause Adams-Oliver syndrome.

Notch signaling determines and reinforces cell fate in bilaterally symmetric multicellular eukaryotes. Despite the involvement of Notch in many key developmental systems, human mutations in Notch signaling components have mainly been described in disorders with vascular and bone effects. Here, we report five heterozygous NOTCH1 variants in unrelated individuals with Adams-Oliver syndrome (AOS), a rare disease with major features of aplasia cutis of the scalp and terminal transverse limb defects. Using whole-genome sequencing in a cohort of 11 families lacking mutations in the four genes with known roles in AOS pathology (ARHGAP31, RBPJ, DOCK6, and EOGT), we found a heterozygous de novo 85 kb deletion spanning the NOTCH1 5' region and three coding variants (c.1285T>C [p.Cys429Arg], c.4487G>A [p.Cys1496Tyr], and c.5965G>A [p.Asp1989Asn]), two of which are de novo, in four unrelated probands. In a fifth family, we identified a heterozygous canonical splice-site variant (c.743-1 G>T) in an affected father and daughter. These variants were not present in 5,077 in-house control genomes or in public databases. In keeping with the prominent developmental role described for Notch1 in mouse vasculature, we observed cardiac and multiple vascular defects in four of the five families. We propose that the limb and scalp defects might also be due to a vasculopathy in NOTCH1-related AOS. Our results suggest that mutations in NOTCH1 are the most common cause of AOS and add to a growing list of human diseases that have a vascular and/or bony component and are caused by alterations in the Notch signaling pathway.

FAN1 mutations cause karyomegalic interstitial nephritis, linking chronic kidney failure to defective DNA damage repair.

Chronic kidney disease (CKD) represents a major health burden. Its central feature of renal fibrosis is not well understood. By exome sequencing, we identified mutations in FAN1 as a cause of karyomegalic interstitial nephritis (KIN), a disorder that serves as a model for renal fibrosis. Renal histology in KIN is indistinguishable from that of nephronophthisis, except for the presence of karyomegaly. The FAN1 protein has nuclease activity and acts in DNA interstrand cross-link (ICL) repair within the Fanconi anemia DNA damage response (DDR) pathway. We show that cells from individuals with FAN1 mutations have sensitivity to the ICL-inducing agent mitomycin C but do not exhibit chromosome breakage or cell cycle arrest after diepoxybutane treatment, unlike cells from individuals with Fanconi anemia. We complemented ICL sensitivity with wild-type FAN1 but not with cDNA having mutations found in individuals with KIN. Depletion of fan1 in zebrafish caused increased DDR, apoptosis and kidney cysts. Our findings implicate susceptibility to environmental genotoxins and inadequate DNA repair as novel mechanisms contributing to renal fibrosis and CKD.

Update of PAX2 mutations in renal coloboma syndrome and establishment of a locus-specific database.

Renal coloboma syndrome, also known as papillorenal syndrome is an autosomal-dominant disorder characterized by ocular and renal malformations. Mutations in the paired-box gene, PAX2, have been identified in approximately half of individuals with classic findings of renal hypoplasia/dysplasia and abnormalities of the optic nerve. Prior to 2011, there was no actively maintained locus-specific database (LSDB) cataloguing the extent of genetic variation in the PAX2 gene and phenotypic variation in individuals with renal coloboma syndrome. Review of published cases and the collective diagnostic experience of three laboratories in the United States, France, and New Zealand identified 55 unique mutations in 173 individuals from 86 families. The three clinical laboratories participating in this collaboration contributed 28 novel variations in 68 individuals in 33 families, which represent a 50% increase in the number of variations, patients, and families published in the medical literature. An LSDB was created using the Leiden Open Variation Database platform: www.lovd.nl/PAX2. The most common findings reported in this series were abnormal renal structure or function (92% of individuals), ophthalmological abnormalities (77% of individuals), and hearing loss (7% of individuals). Additional clinical findings and genetic counseling implications are discussed.

Familial mental retardation due to a cryptic subtelomeric translocation -del 14qter and dup 9qter (the Anyon phenotype).

An example of familial mental retardation is described in which there is a distinctive phenotype. It consists of IQ in the 30-50 range, microcephaly, short stature, narrow skull, prominent ears and nose and a cryptic subtelomeric translocation resulting in del 14qter and dup 9qter. Variable features include congenital heart disease, peripheral neuropathy and epilepsy. The phenotype was described in 1965 by Anyon.

Floating-Harbor syndrome complicated by tethered cord: a new association and potential contribution from growth hormone therapy.

Floating-Harbor syndrome is a rare syndrome with short stature, severely delayed bone age, typical facies and delay in expressive speech. Structural malformations are uncommon, and tethered cord or other forms of spinal dysraphism have not previously been reported. We report on a case of Floating-Harbor syndrome, complicated by tethered cord and discuss the possibility that growth hormone therapy may contribute to the development of symptoms of this malformation.

De novo mutations in the mitochondrial ND3 gene as a cause of infantile mitochondrial encephalopathy and complex I deficiency.

Both nuclear and mitochondrial DNA mutations can cause energy generation disorders. Respiratory chain complex I deficiency is the most common energy generation disorder and a frequent cause of infantile mitochondrial encephalopathies such as Leigh's disease and lethal infantile mitochondrial disease. Most such cases have been assumed to be caused by nuclear gene defects, but recently an increasing number have been shown to be caused by mutations in the mitochondrially encoded complex I subunit genes ND4, ND5, and ND6. We report the first four cases of infantile mitochondrial encephalopathies caused by mutations in the ND3 subunit gene. Three unrelated children have the same novel heteroplasmic mutation (T10158C), only the second mutation reported in ND3, and one has the previously identified T10191C mutation. Both mutations cause disproportionately greater reductions in enzyme activity than in the amount of fully assembled complex I, suggesting the ND3 subunit plays an unknown but important role in electron transport, proton pumping, or ubiquinone binding. Three cases appear to have a de novo mutation, with no mutation detected in maternal relatives. Mitochondrial DNA disease may be considerably more prevalent in the pediatric population than currently predicted and should be considered in patients with infantile mitochondrial encephalopathies and complex I deficiency.