Homozygous microdeletion of exon 5 in ZNF277 in a girl with specific language impairment

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The Genetics Journey: A Case Report of a Genetic Diagnosis Made 30 Years Later

Mandibulofacial dysostosis with microcephaly (MFDM) is a rare autosomal dominant condition that was first described in 2006. The causative gene, EFTUD2, identified in 2012. We report on a family that initially presented to a pediatric genetics clinic in the 1980s for evaluation of multiple congenital anomalies. Re‐evaluation of one member thirty years later resulted in a phenotypic and molecularly confirmed diagnosis of MFDM. This family’s clinical histories and the novel EFTUD2 variant identified, c.1297_1298delAT (p.Met433Valfs*17), add to the literature about MFDM. This case presented several genetic counseling challenges and highlights that “the patient” can be multiple family members. We discuss testing considerations for an unknown disorder complicated by the time constraint of the patient’s daughter’s pregnancy and how the diagnosis changed previously provided recurrence risks. Of note, 1) the 1980s clinic visit letters provided critical information about affected family members and 2) the patient’s husband’s internet search of his wife’s clinical features also yielded the MFDM diagnosis, illustrating the power of the internet in the hands of patients. Ultimately, this case emphasizes the importance of re‐evaluation given advances in genetics and the value of a genetic diagnosis for both patient care and risk determination for family members.Peer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/147210/1/jgc40894.pd

Pre-operative preparation of patients for total knee replacement: An action research study

Aims and objectives: To examine the development and impact of a multidisciplinary preparation clinic for patients undergoing total knee replacement (TKR) surgery. Background: There is evidence to suggest that patients’ preoperative characteristics such as pain and mental state impact the long term results of TKR surgery. Preparation sessions may help in identifying and working with those patients whose preoperative status could reduce the benefits of surgery. Design: Action research. Method: Actions cycles were carried out to develop an information booklet and multidisciplinary Knee Clinic at an acute Trust in outer London, UK. A sample (n = 23) of patients was recruited to test changes as they were implemented. Results: The Knee Clinic involved nurse practitioners, occupational therapists, physiotherapists and service users (patients recovered from TKR surgery). Elements of physical and social assessment and interventions were carried out using a Social Cognitive Theory framework. Patients reported they benefitted from the information booklet and attendance at the Knee Clinic. Conclusion: A structured pre-operative information and assessment clinic can be developed using a Social Cognitive Theory framework for the benefit of patients. Further studies are required to examine and utilise psychological assessment of patients at such clinics

Cloning and characterization of a novel alternatively spliced transcript of the human CHD7 putative helicase

<p>Abstract</p> <p>Background</p> <p>The <it>CHD7 </it>(Chromodomain Helicase DNA binding protein 7) gene encodes a member of the chromodomain family of ATP-dependent chromatin remodeling enzymes. Mutations in the <it>CHD7 </it>gene are found in individuals with CHARGE, a syndrome characterized by multiple birth malformations in several tissues. CHD7 was identified as a binding partner of PBAF complex (Polybromo and BRG Associated Factor containing complex) playing a central role in the transcriptional reprogramming process associated to the formation of multipotent migratory neural crest, a transient cell population associated with the genesis of various tissues. <it>CHD7 </it>is a large gene containing 38 annotated exons and spanning 200 kb of genomic sequence. Although genes containing such number of exons are expected to have several alternative transcripts, there are very few evidences of alternative transcripts associated to <it>CHD7 </it>to date indicating that alternative splicing associated to this gene is poorly characterized.</p> <p>Findings</p> <p>Here, we report the cloning and characterization by experimental and computational studies of a novel alternative transcript of the human <it>CHD7 </it>(named CHD7 CRA_e), which lacks most of its coding exons. We confirmed by overexpression of CHD7 CRA_e alternative transcript that it is translated into a protein isoform lacking most of the domains displayed by the canonical isoform. Expression of the CHD7 CRA_e transcript was detected in normal liver, in addition to the DU145 human prostate carcinoma cell line from which it was originally isolated.</p> <p>Conclusions</p> <p>Our findings indicate that the splicing event associated to the CHD7 CRA_e alternative transcript is functional. The characterization of the CHD7 CRA_e novel isoform presented here not only sets the basis for more detailed functional studies of this isoform, but, also, contributes to the alternative splicing annotation of the <it>CHD7 </it>gene and the design of future functional studies aimed at the elucidation of the molecular functions of its gene products.</p

SNP genotyping to screen for a common deletion in CHARGE Syndrome

BACKGROUND: CHARGE syndrome is a complex of birth defects including coloboma, choanal atresia, ear malformations and deafness, cardiac defects, and growth delay. We have previously hypothesized that CHARGE syndrome could be caused by unidentified genomic microdeletion, but no such deletion was detected using short tandem repeat (STR) markers spaced an average of 5 cM apart. Recently, microdeletion at 8q12 locus was reported in two patients with CHARGE, although point mutation in CHD7 on chromosome 8 was the underlying etiology in most of the affected patients. METHODS: We have extended our previous study by employing a much higher density of SNP markers (3258) with an average spacing of approximately 800 kb. These SNP markers are diallelic and, therefore, have much different properties for detection of deletions than STRs. RESULTS: A global error rate estimate was produced based on Mendelian inconsistency. One marker, rs431722 exceeded the expected frequency of inconsistencies, but no deletion could be demonstrated after retesting the 4 inconsistent pedigrees with local flanking markers or by FISH with the corresponding BAC clone. Expected deletion detection (EDD) was used to assess the coverage of specific intervals over the genome by deriving the probability of detecting a common loss of heterozygosity event over each genomic interval. This analysis estimated the fraction of unobserved deletions, taking into account the allele frequencies at the SNPs, the known marker spacing and sample size. CONCLUSIONS: The results of our genotyping indicate that more than 35% of the genome is included in regions with very low probability of a deletion of at least 2 Mb

High frequency of CHD7 mutations in congenital hypogonadotropic hypogonadism

Congenital hypogonadotropic hypogonadism (CHH) is characterized by lack of normal pubertal development due to deficient gonadotropin-releasing hormone (GnRH) secretion or action, and is caused by genetic defects in several genes. Mutations in the CHD7 gene cause CHARGE syndrome (Coloboma of the eye, Heart defects, Atresia of the choanae, Retardation of growth and development, Genital hypoplasia and Ear abnormalities), but have also been found in patients with isolated CHH. The aim of this study was to identify CHD7 mutations in patients with CHH. Fifty Portuguese patients with CHH were screened for mutations in the CHD7 gene by DNA sequencing. Eight (16%) patients had CHD7 rare sequence variants that consisted of six missense (p.Gly388Glu, p.His903Pro, p.Thr1082Ile, p.Val1452Leu, p.Asp1854Gly, and p.Arg2065His) and two synonymous (p.Ser559Ser, and p.Ala2785Ala) mutations. Five of these mutations have never been reported before. Three CHD7 mutations occurred in patients that had mutations in additional CHH-genes. This study uncovered novel genetic variants that expand the known spectrum of mutations associated with CHH. The frequency of CHD7 mutations in this cohort was higher than that of other major CHH-genes and confirms the importance of including CHD7 in the genetic testing of CHH, even in the absence of additional CHARGE features.info:eu-repo/semantics/publishedVersio

CHD7 Mutational Analysis and Clinical Considerations for Auditory Rehabilitation in Deaf Patients with CHARGE Syndrome

BACKGROUND: Otologic manifestations are one of the most consistent findings of CHARGE syndrome found in more than 90%. Since genetic analysis of the CHD7 gene has rarely been performed in previous reports dealing with ear abnormalities, the genotypic spectrum of CHD7 mutations was analyzed in deaf patients with CHARGE syndrome, and the clinical considerations concerning auditory rehabilitation were investigated. METHODS: Nine Korean patients with CHARGE syndrome showing profound hearing loss and semicircular canal aplasia were included. All 38 exons of CHD7 were analyzed by direct sequencing. For splice site variations, in silico and exon-trapping analyses were performed to verify the pathogenicity of nucleotide variations. Clinical features and the outcome of auditory rehabilitation were also analyzed. RESULTS: Eight of 9 patients revealed alterations of the CHD7 gene including 3 frameshift, 2 nonsense, 2 splice site, and 1 missense mutations. Five of 9 patients were clinically diagnosed as atypical CHARGE syndrome but demonstrated various mutations of the CHD7 gene. One familial case showed intra-familial variability. Radiologic findings suggesting cochleovestibular nerve deficiency were identified in most of the patients. Of the 8 patients who underwent cochlear implantation, 5 patients demonstrated favorable outcome. Larger diameter of the cochleovestibular nerve on imaging and absence of severe mental retardation were factors related to better outcome after cochlear implantation rather than the type of CHD7 mutations. Auditory brainstem implantation was performed in two patients who did not benefit from cochlear implantation. CONCLUSIONS: Genetic analysis of the CHD7 gene should be performed in cases with semicircular canal aplasia even when other typical features of CHARGE syndrome are absent. For auditory rehabilitation in CHARGE syndrome, cochlear implantation should be strongly recommended in selected cases with favorable prognostic factors. Auditory brainstem implantation may be a viable option in patients with CHARGE syndrome who have failed to benefit from cochlear implantation