MYH7 Research Articles

Hereditary thrombocytopenia with familial novel mutation in MYH9 gene: A familial case report

One of the rarest types of hereditary thrombocytopenia is the MYH9-related disorder. This spectrum of disorders is characterized by large platelets with or without leukocyte inclusion bodies, a decrease in the total number of platelets, and autosomal dominant inheritance. Proteinuric nephropathy that frequently progresses to end-stage renal failure, as well as the beginning of progressive high-frequency sensorineural hearing loss in young adults, is also associated with MYH9-related disorder. In this case report, we presented three family members who had thrombocytopenia and in whom a heterozygous novel 22 bp deletion (c.4274_4295del) was detected which is located in exon 31 of the MYH9 gene. There was no evidence of bleeding in the family members we presented and thrombocytopenia was detected incidentally. Additionally, renal failure, hearing loss, presenile cataracts, and clinical symptoms were not detected in these family members. This novel mutation detected in the MYH9 gene has not been reported in the literature before.

Case report: a 55-year-old patient with hypertrophic cardiomyopathy and heterozygous missense variant of TTN and MYH6 genes

Case report: a 55-year-old patient with hypertrophic cardiomyopathy and heterozygous missense variant of TTN and MYH6 genes

Phenotypic expressions of a novel mutation in the MYH7 gene responsible for hypertrophic cardiomyopathy in Pune population

Introduction and Aim: Hypertrophic cardiomyopathy (HCM) are the most common kind of cardiac disease that causes left ventricular asymmetric hypertrophy (LVH) or right ventricular hypertrophy (RVH) and non-dilated ventricular chambers. Heterozygous mutation in the MYH7 gene on chromosome 14 causes Left ventricular hypertrophy. The objective of our study was to unravel the mutation spectrum in HCM positive patients and find out novel mutation in MYH7 gene and the impact of these mutations on the pathophysiology of cardiac functioning. Materials and Methods: Identification and confirmation of HCM patients was done on the basis of the thickness of the Interventricular septum and Left ventricular wall ( >13mm ; >15mm ). Extraction of DNA from the whole blood of HCM patients and healthy population using the standard phenol- chloroform extraction method was carried out. Polymerase Chain Reaction (PCR) was performed, and samples were processed for Sanger sequencing. Alter the structural arrangement and characteristics of respective mRNAs software’s RNA Fold Web server. Results: We found a novel mutation in the MYH7 gene, which could cause phenotypic expressions similar to that of HCM. Conclusion: Mutation in the gene may be responsible for causing hypertrophic cardiomyopathy. The mutations reported in our study, are responsible to alter the structural arrangement and characteristics of respective mRNAs.

Prenatal diagnosis of recurrent hypoplastic left heart syndrome associated with MYH6 variants: a case report

BackgroundHypoplastic left heart syndrome (HLHS) is a rare but genetically complex and clinically and anatomically severe form of congenital heart disease (CHD).Case presentationHere, we report on the use of rapid prenatal whole-exome sequencing for the prenatal diagnosis of a severe case of neonatal recurrent HLHS caused by heterozygous compound variants in the MYH6 gene inherited from the (healthy) parents. MYH6 is known to be highly polymorphic; a large number of rare and common variants have variable effects on protein levels. We postulated that two hypomorphic variants led to severe CHD when associated in trans; this was consistent with the autosomal recessive pattern of inheritance. In the literature, dominant transmission of MYH6-related CHD is more frequent and is probably linked to synergistic heterozygosity or the specific combination of a single, pathogenic variant with common MYH6 variants.ConclusionsThe present report illustrates the major contribution of whole-exome sequencing (WES) in the characterization of an unusually recurrent fetal disorder and considered the role of WES in the prenatal diagnosis of disorders that do not usually have a genetic etiology.

MicroRNA regulation of skin pigmentation in golden-back mutant of crucian carp from a rice-fish integrated farming system

BackgroundMicroRNAs (miRNAs) are endogenous small non-coding RNAs (21–25 nucleotides) that act as essential components of several biological processes. Golden-back crucian carp (GBCrC, Carassius auratus) is a naturally mutant species of carp that has two distinct body skin color types (golden and greenish-grey), making it an excellent model for research on the genetic basis of pigmentation. Here, we performed small RNA (sRNA) analysis on the two different skin colors via Illumina sequencing.ResultsA total of 679 known miRNAs and 254 novel miRNAs were identified, of which 32 were detected as miRNAs with significant differential expression (DEMs). 23,577 genes were projected to be the targets of 32 DEMs, primarily those involved in melanogenesis, adrenergic signaling in cardiomyocytes, MAPK signaling pathway and wnt signaling pathway by functional enrichment. Furthermore, we built an interaction module of mRNAs, proteins and miRNAs based on 10 up-regulated and 13 down-regulated miRNAs in golden skin. In addition to transcriptional destabilization and translational suppression, we discovered that miRNAs and their target genes were expressed in the same trend at both the transcriptional and translational levels. Finally, we discovered that miR-196d could be indirectly implicated in regulating melanocyte synthesis and motility in the skin by targeting to myh7 (myosin-7) gene through the luciferase reporter assay, antagomir silencing in vivo and qRT-PCR techniques.ConclusionsOur study gives a systematic examination of the miRNA profiles expressed in the skin of GBCrC, assisting in the comprehension of the intricate molecular regulation of body color polymorphism and providing insights for C. auratus breeding research.

Myosin post-translational modifications and function in the presence of myopathy-linked truncating MYH2 mutations.

Congenital myopathies are a vast group of genetic muscle diseases. Among the causes are mutations in the MYH2 gene resulting in truncated type IIa myosin heavy chains (MyHCs). The precise cellular and molecular mechanisms by which these mutations induce skeletal muscle symptoms remain obscure. Hence, in the present study, we aimed to explore whether such genetic defects would alter the presence as well as the post-translational modifications of MyHCs and the functionality of myosin molecules. For this, we dissected muscle fibers from four myopathic patients with MYH2 truncating mutations and from five human healthy controls. We then assessed 1) MyHCs presence/post-translational modifications using LC/MS; 2) relaxed myosin conformation and concomitant ATP consumption with a loaded Mant-ATP chase setup; 3) myosin activation with an unloaded in vitro motility assay; and 4) cellular force production with a myofiber mechanical setup. Interestingly, the type IIa MyHC with one additional acetylated lysine (Lys35-Ac) was present in the patients. This was accompanied by 1) a higher ATP demand of myosin heads in the disordered-relaxed conformation; 2) faster actomyosin kinetics; and 3) reduced muscle fiber force. Overall, our findings indicate that MYH2 truncating mutations impact myosin presence/functionality in human adult mature myofibers by disrupting the ATPase activity and actomyosin complex. These are likely important molecular pathological disturbances leading to the myopathic phenotype in patients.

Embryonic myosin mutations alter the mechanics and maturation of HiPSC derived skeletal muscle.

Distal arthrogryposis (DA) is a skeletal muscle disorder characterized by joint contractures predominantly localized in the distal extremities. DA associated syndromes like Freeman-Sheldon syndrome (FSS) are linked to mutations in the MYH3 gene that encodes the embryonic skeletal muscle myosin. To study the mutation and its effect on developing muscle, we generated human induced pluripotent stem cell (hiPSC) lines bearing T178I or R672C MYH3 mutations. hiPSC were differentiated into skeletal muscle and evaluated for differences in the maturation of the contractile unit and its functional performance. Preliminary myofibril mechanics measurements showed T178I myotubes generated significantly greater specific force compared to control myofibrils. Diseased myofibrils also expressed significantly slower rates of relaxation and prolonged thin filament deactivation compared to control myofibrils. Myofibril preparations were also used to compare ATP binding rates across conditions. Preliminary results showed homozygous R672C myofibrils have faster ATP binding rates compared to heterozygous and control preparations. Mutations in MYH3 were also associated with alterations in myosin isoform content, with homozygous R672C having reduced MYH3 levels in day 7 cells. Molecular dynamics simulations of R672C and T178I mutations in the post rigor state showed greater separation between the beta-sheet and SH-helix than in controls. Mutation also disrupted local salt bridges and hydrogen bond formation in some residues that help stabilize the nucleotide binding pocket and converter-connected helix. Interrupted structural communication between the nucleotide binding pocket and surrounding functional regions may underly the impaired relaxation phenotype. Ongoing studies will further characterize the effect of mutation on actin-myosin binding, crossbridge cycling kinetics, the maturation of skeletal myotubes over time, and myosin isoform switching dynamics.

Expanding the phenotypic spectrum of Chromosome 16p13.11 microduplication: A multicentric analysis of 206 patients

IntroductionRecurrent chromosome 16p13.11 microduplication has been characterised in the literature as a cause of developmental delay, learning difficulties and behavioural abnormalities. It is a neurosusceptibility locus and has incomplete penetrance and variable expression. Other clinical features, such as cardiac abnormalities have also been reported. The duplicated region contains the MYH11 gene, which encodes the protein myosin-11 and is a component of the myosin heavy chain in smooth muscle. Recent literature has suggested 16p13.11 microduplication as one of the possible risk factors for thoracic aortic aneurysms and dissection (TAAD). Therefore, we studied the detailed phenotype of cases of chromosome 16p13.11 microduplication from seven centres in the United Kingdom (UK) to expand the phenotype, focusing on the cardiac abnormalities. MethodsAll individuals with a chromosome 16p13.11 microduplication seen in Clinical Genetics prior to June 2017 in 6 centres (prior to 2018 in the seventh centre) were identified through the regional genetics laboratory databases. A Microsoft Excel® proforma was created and clinical data was collected retrospectively from clinical genetics databases from the seven genetics services in the UK. The data was collated and analysed collectively. ResultsThe majority of the individuals presented with (72%) developmental delay and (62%) behavioural abnormalities, in keeping with the published literature. 27% had some dysmorphic features, 14% had visual impairment and 8% had congenital cardiac abnormalities. Echocardiograms were performed in 50% of patients, and only 3.8% patients had aortic dilatation and no one had aortic dissection. 9.7% of patients were found to have a second genetic/chromosomal diagnosis, especially where there were additional phenotypic features. Conclusion16p13.11 microduplication is a neurosusceptibility locus and is associated with variable expression. It may be helpful to refer children with 16p13.11 microduplication for a cardiac review for congenital cardiac abnormalities and also for ophthalmological assessment. Further prospective studies with cardiac assessments are recommended in this cohort of patients to determine whether ongoing aortic surveillance is indicated. Guidelines about the frequency of surveillance are indicated, especially in individuals with normal cardiac findings. We also highlight the importance of considering a second diagnosis if the phenotype is inconsistent with that reported.

Genetic Analysis of Variants of the MYH6 Gene Promoter in Congenital Atrial Septal Defects

Background: Atrial septal defect (ASD) is one of the common congenital heart diseases. The MYH6 gene has a critical role in cardiac development but the role of MYH6 promoter variants in patients with ASD has not been explored. Methods: In 613 subjects including 320 ASD patients, we investigated the MYH6 gene promoter variants and verified the effect on gene expression by using cellular functional experiments and bioinformatics analysis. Results: Eleven variants were identified in the MYH6 gene promoter, of which four variants were found only in ASD patients, and two variants (g.3434G>C and g.4524C>T) were identified for the first time. Cellular functional experiments indicated that all four variants reduced the transcriptional activity of the MYH6 gene promoter (p < 0.05). Subsequent analysis through the JASPAR (A database of transcription factor binding profiles) suggests that these variants may alter transcription factor binding sites, which may in turn lead to changes in myocardin subunit expression and ASD formation. Conclusions: Our study for the first time focuses on variants in the promoter region of the MYH6 gene in Chinese patients with ASD and the discovered variants have functional significance. The study provides new insights in the role of the MYH6 gene promoter region to better understand the genetic basis of ASD formation and facilitates clinical diagnosis.

Sarcomeric gene variants among Indians with hypertrophic cardiomyopathy: A scoping review.

Hypertrophic cardiomyopathy (HCM) is a genetic heart muscle disease that frequently causes sudden cardiac death (SCD) among young adults. Several pathogenic mutations in genes encoding the cardiac sarcomere have been identified as diagnostic factors for HCM and proposed as prognostic markers for SCD. The objective of this review was to determine the scope of available literature on the variants encoding sarcomere proteins associated with SCD reported among Indian patients with HCM. The eligibility criteria for the scoping review included full text articles that reported the results of genetic screening for sarcomeric gene mutations in HCM patients of Indian south Asian ancestry. We systematically reviewed studies from the databases of Medline, Scopus, Web of Science core collection and Google Scholar. The electronic search strategy included a combination of generic terms related to genetics, disease and population. The protocol of the study was registered with Open Science Framework (https://osf.io/53gde/). A total of 19 articles were identified that reported pathogenic or likely pathogenic (P/LP) variants within MYH7, MYBPC3, TNNT2, TNNI3 and TPM1 genes, that included 16 singletons, one de novo and one digenic mutation (MYH7/ TPM1) associated with SCD among Indian patients. Evidence from functional studies and familial segregation implied a plausible mechanistic role of these P/LP variants in HCM pathology. This scoping review has compiled all the P/LP variants reported to-date among Indian patients and summarized their association with SCD. Single homozygous, de novo and digenic mutations were observed to be associated with severe phenotypes compared to single heterozygous mutations. The abstracted genetic information was updated with reference sequence ID (rsIDs) and compiled into freely accessible HCMvar database, available at https://hcmvar.heartfailure.org.in/. This can be used as a population specific genetic database for reference by clinicians and researchers involved in the identification of diagnostic and prognostic markers for HCM.

Myh6 promoter-driven Cre recombinase excises floxed DNA fragments in a subset of male germline cells

Myh6-Cre transgenic mouse line was known to express Cre recombinase only in the heart. Nevertheless, during breeding Myh6-Cre to Rosa26fstdTom reporter (tdTom) mouse line, we observed that a significant part of their F2 tdTom/+ offspring had tdTom reporter gene universally activated. Our results show that Myh6-Cre transgenic mice have Cre recombinase activity in a subpopulation of the male germline cells, and that Myh6 gene transcripts are enriched in the interstitial Leydig cells and the undifferentiated spermatogonia stem cells. In summary, the current study confirms that the previously known “heart-specific” Myh6 promoter drives Cre expression in the testis.

Letter: Nationwide Readmission Rates and Hospital Charges for Patients With Surgical Evacuation of Nontraumatic Subdural Hematomas: Part 1-Craniotomy.

Letter: Nationwide Readmission Rates and Hospital Charges for Patients With Surgical Evacuation of Nontraumatic Subdural Hematomas: Part 1-Craniotomy.

903 NOVEL MALIGNANT MUTATION IN HYPERTROPHIC CARDIOMYOPATHY

Abstract Background Hypertrophic cardiomyopathy (HCM) is a common inherited disease almost invariably caused by mutations in sarcomeric genes. The HCM phenotype is clinically heterogeneous with myocyte hypertrophy, disarray, and myocardial fibrosis as histological hallmarks. This condition is recognized as an important cause of sudden cardiac death (SCD) in the youth and of heart failure (HF) in the elderly. Current guidelines mandate genetic analysis as a class I indication in HCM. Indeed, the advent of the next generation sequencing in the medical practice has led to decipher the molecular etiology of HCM and to assess the disease risk in family members with relevant insights into the clinical course. Clinical case A 62-year-old man followed-up at another Hospital with a non-obstructive HCM diagnosis, was referred to our Hospital for therapy optimization and clinical follow-up. Past medical history included third degree atrioventricular block at age 40 treated with dual chamber pacemaker (PM) and, at age of 60, atrial flutter with high ventricular response complicated with cardiogenic shock and stroke. Due to worsening systolic function and ventricular sustained tachycardia he was upgraded to implantable cardioverter defibrillator which delivered appropriate shocks. Echocardiography performed during current hospitalization showed a moderate concentric hypertrophy (intraventricular septum 17 mm, cardiac mass index 258 g/m2), dilated ventricle with reduced ejection fraction (33%) and akinesis of the mid inferior and infero-septal walls of the left ventricle and of the apex, with a stratified thrombotic apposition. Magnetic resonance was contraindicated because of non-compatible PM. Due to alteration in serum proteins and free light chain, to rule out systemic disease, extensive imaging diagnosis was performed including bone scintigraphy and abdominal ultrasonography which resulted negative. While waiting for bone marrow aspiration and biopsy the patient rapidly deteriorated with worsening renal failure, ensuing proteinuria until exitus. After an appropriate pre-test counseling the family consented to genetic test in the proband. Clinical exome sequencing revealed the presence of a missense mutation in MYH7 gene. This new mutation is characterized by the substitution of cysteine residue by a serine in 905 codon of MYH7 gene. Cys905Ser results in a semi-conservative amino acid substitution which may impact disulfide bond formation in the MYH7 protein. To date no study has described this mutation as a cause of HCM. A mutation affecting this same codon, Cys905Phe was reported in only one patient with HCM. From a biological point of view, this variant lies in the head region of the protein where the majority of the missense variants are grouped and statistically associated to HCM phenotype. Several studies reported that the occurrence of atrial fibrillation (AF) tends to be more prevalent in patients carrying the MYH7 mutation. Furthermore, AF is associated with substantial risk for HF-related mortality, stroke, and severe functional disability. Awareness regarding the spectrum of MYH7 mutations probably related to SCD or HF combined with a thorough patient characterization for molecular and clinical features, may help to improve the genotype and phenotype correlation. This important challenge could elucidate better the mechanism of HCM enabling cardiologists to a better clinical decision-making and patients’ care.

Genetic variants, clinical characteristics and outcomes of non-compaction cardiomyopathy

Aim. Evaluate clinical and structural-functional characteristics, including adverse events and outcomes, in patients with non-compact cardiomyopathy (NCM) with various genetic variants.Material and Methods. 51 unrelated patients with NCM were examined (mean age 37 [28; 47]; men (54.9%), women (45.1%)), observed for 7 to 211 months (in average 38 months). Clinical and instrumental examination included checkup, collection of individual and family history, ECG-12 registration, 24-hour Holter ECG monitoring, echocardiography, magnetic resonance imaging (MRI) of the heart with late contrast enhancement. The search for mutations in the coding sequences of 174 genes associated with cardiovascular pathology was carried out by high-throughput sequencing (NGS).Results and discussion. In 24 of 51 (47.1%) patients, 27 mutations of pathogenicity classes IV and V were detected, while in 21 (41.2%) patients, mutations were in the genes of sarcomeric proteins, of which 37.5% were in the MYBPC3 gene, 25.0% in the MYH7 gene, and in the TTN gene, leading to a shortened protein (TTNtv) – 33.3%, there is a mutation in the ACTC1 – 1 gene (4.2%). In 5.9% of patients, mutations were detected in genes encoding structural proteins and ion channel subunits. Two or more genetic variants were found in 10 out of 24 (41.7%) patients. No significant genetic variants were identified in 14 (27.4%) patients. Patients with mutations in the TTNtv gene were associated with severe systolic dysfunction, dilation of the left ventricle. Carriers of mutations in the MYBPC3 gene and several genetic variants were more likely to have adverse events and outcomes: progression of chronic heart failure (CHF), ventricular tachyarrhythmias, sudden cardiac death (SCD) with successful resuscitation, mortality. Patients with mutations in the MYH7 gene had no adverse outcomes.Conclusion. Comparative analysis showed that patients with NCM had the most severe form of the disease with significant clinical manifestations, episodes of clinical death with subsequent resuscitation and cardioverter defibrillator implantation in probands with mutations in TTNtv gene, mutations in the MYBPC3 gene or multiple genetic variants.

Detection of the Copy Number Variants of Genes in Patients with Familial Cardiac Diseases by Massively Parallel Sequencing.

The implication of copy number variations in familial heart disease is known, although in-depth knowledge is lacking; hence, more studies are needed to further our understanding. Massively parallel sequencing, thanks to its recent surge in use, is emerging as a valid tool for the detection of this type of variant, through the use of appropriate software. We conducted a study with 182 patients diagnosed with mendelian cardiovascular diseases who underwent sequencing using a cardiac gene panel and then a specific calling process for copy number variations (CNVs) with ExomeDepth software, which provides us with a Bayes factor (BF), a score of the probability that a CNV detected is true. After a rigorous CNV prioritization process, we confirmed the variants obtained by MLPA or SNP-based array, finding three real CNVs in five individuals in the MYH11, FBN1 and PDMI7 genes. The confirmed CNVs present in all cases BF values >60, thus establishing a threshold to consider real CNVs in the calling process carried out by ExomeDepth on our gene panel.

A familial case of MYH9 gene mutation associated with multiple functional and structural platelet abnormalities

Mutations in the MYH9 gene result in macrothrombocytopenia often associated with hemorrhages. Here, we studied the function and structure of platelets in three family members with a heterozygous mutation R1933X in the MYH9 gene, characteristic of closely related disorders known as the May-Hegglin anomaly and Sebastian syndrome. The examination included complete blood count, blood smear microscopy, platelet flow cytometry (expression of P-selectin and active integrin αIIbβ3 before and after activation), the kinetics of platelet-driven contraction (retraction) of blood clots, as well as scanning/transmission electron microscopy of platelets. Despite severe thrombocytopenia ranging (36–86) × 109/l, none of the patients had hemorrhages at the time of examination, although they had a history of heavy menstruation, spontaneous ecchymosis, and postpartum hemorrhage. Flow cytometry showed background platelet activation, revealed by overexpression of P-selectin and active αIIbβ3 integrin above normal levels. After TRAP-induced stimulation, the fractions of platelets expressing P-selectin in the proband and her sister were below normal response, indicating partial platelet refractoriness. The initiation of clot contraction was delayed. Electron microscopy revealed giant platelets with multiple filopodia and fusion of α-granules with dilated open canalicular system, containing filamentous and vesicular inclusions. The novel concept implies that the R1933X mutation in the MYH9 gene is associated not only with thrombocytopenia, but also with qualitative structural and functional defects in platelets. Platelet dysfunction includes impaired contractility, which can disrupt the compaction of hemostatic clots, making the clots weak and permeable, therefore predisposing patients with MYH9 gene mutations to the hemorrhagic phenotype.

Bisphenols induce cardiotoxicity in zebrafish embryos: Role of the thyroid hormone receptor pathway

Bisphenols are frequently found in the environment and have been of emerging concern because of their adverse effects on aquatic animals and humans. In this study, we demonstrated that bisphenol A, S, and F (BPA, BPS, BPF) at environmental concentrations induced cardiotoxicity in zebrafish embryos. BPA decreased heart rate at 96 hpf (hours post fertilization) and increased the distance between the sinus venosus (SV) and bulbus arteriosus (BA), in zebrafish. BPF promoted heart pumping and stroke volume, shortened the SV-BAdistance, and increased body weight. Furthermore, we found that BPA increased the expression of the dio3b, thrβ, and myh7 genes but decreased the transcription of dio2. In contrast, BPF downregulated the expression of myh7 but upregulated that of thrβ. Molecular docking results showed that both BPA and BPF are predicted to bind tightly to the active pockets of zebrafish THRβ with affinities of -4.7 and -4.77 kcal/mol, respectively. However, BPS did not significantly affect dio3b, thrβ, and myh7 transcription and had a higher affinity for zebrafish THRβ (-2.13 kcal/mol). These findings suggest that although BPA, BPS, and BPF have similar structures, they may induce cardiotoxicity through different molecular mechanisms involving thyroid hormone systems. This investigation provides novel insights into the potential mechanism of cardiotoxicity from the perspective of thyroid disruption and offer a cautionary role for the use of BPA substitution.

Pancreatic Cancer Cell-Conditioned, Human-Derived Primary Myotubes Display Increased Leucine Turnover, Increased Lipid Accumulation, and Reduced Glucose Uptake.

Metabolic alterations occurring in cancer cells have been seen to also occur in other tissues than cancerous tissue. For instance, cachexia, peripheral insulin resistance, or both are commonly seen in patients with cancer. We explored differences in substrate use in myotubes conditioned with the medium from a pancreatic cancer cell line, PANC-1, or primary human pancreatic cells, hPECs. Protein turnover was assessed using scintillation proximity assay, glucose and oleic acid handling were analyzed by substrate oxidation assay. We performed qPCR to study gene expression and immunoblotting and proteomic analyses to study protein expression. PANC-1-conditioned myotubes had an imbalance in protein turnover with decreased accumulation, increased decay, and decreased MYH2 gene expression. Glucose uptake decreased despite increased insulin-stimulated Akt phosphorylation. Fatty acid uptake increased, whereas fatty acid oxidation was unchanged, leading to accumulation of intracellular lipids (TAG) in PANC-1-conditioned myotubes. Secretome analyses revealed increased release of growth factors and growth factor receptor from PANC-1 cells, potentially affecting muscle cell metabolism. Myotubes exposed to pancreatic cancer cell medium displayed altered energy metabolism with increased protein/leucine turnover and lipid accumulation, while glucose uptake and oxidation reduced. This indicates production and release of substances from pancreatic cancer cells affecting skeletal muscle.

Machine learning with in silico analysis markedly improves survival prediction modeling in colon cancer patients.

Predicting the survival of cancer patients provides prognostic information and therapeutic guidance. However, improved prediction models are needed for use in diagnosis and treatment. This study aimed to identify genomic prognostic biomarkers related to colon cancer (CC) based on computational data and to develop survival prediction models. We performed machine-learning (ML) analysis to screen pathogenic survival-related driver genes related to patient prognosis by integrating copy number variation and gene expression data. Moreover, in silico system analysis was performed to clinically assess data from ML analysis, and we identified RABGAP1L, MYH9, and DRD4 as candidate genes. These three genes and tumor stages were used to generate survival prediction models. Moreover, the genes were validated by experimental and clinical analyses, and the theranostic application of the survival prediction models was assessed. RABGAP1L, MYH9, and DRD4 were identified as survival-related candidate genes by ML and in silico system analysis. The survival prediction model using the expression of the three genes showed higher predictive performance when applied to predict the prognosis of CC patients. A series of functional analyses revealed that each knockdown of three genes reduced the protumor activity of CC cells. In particular, validation with an independent cohort of CC patients confirmed that the coexpression of MYH9 and DRD4 gene expression reflected poorer clinical outcomes in terms of overall survival and disease-free survival. Our survival prediction approach will contribute to providing information on patients and developing a therapeutic strategy for CC patients.

Mutation of the MYH3 gene causes recessive cleft palate in Limousine cattle

BackgroundThe palate is a structure separating the oral and nasal cavities and its integrity is essential for feeding and breathing. The total or partial opening of the palate is called a cleft palate and is a common malformation in mammals with environmental or hereditary aetiologies. Generally, it compromises life expectancy in the absence of surgical repair. A new form of non-syndromic cleft palate arose recently in Limousine cattle, with animals referred to the French National Observatory of Bovine Abnormalities since 2012. Since the number of affected animals has increased steadily, this study was undertaken to identify the cause of this disease.ResultsBased on pedigree analysis, occurrence of cleft palate in Limousine cattle was concordant with an autosomal recessive mode of inheritance. Genotyping of 16 affected animals and homozygosity mapping led to the identification of a single disease-associated haplotype on Bos taurus chromosome (BTA)19. The genome of two affected animals was sequenced, and their sequences were compared to the ARS-UCD1.2 reference genome to identify variants. The likely causal variants were compared to the variant database of the 1000 bull genome project and two fully linked mutations in exon 24 of the MYH3 (myosin heavy chain) gene were detected: a 1-bp non-synonymous substitution (BTA19:g.29609623A>G) and a 11-bp frameshift deletion (BTA19:g.29609605-29609615del). These two mutations were specific to the Limousine breed, with an estimated allele frequency of 2.4% and are predicted to be deleterious. The frameshift leads to a premature termination codon. Accordingly, mRNA and protein analyses in muscles from wild-type and affected animals revealed a decrease in MYH3 expression in affected animals, probably due to mRNA decay, as well as an absence of the MYH3 protein in these animals. MYH3 is mostly expressed in muscles, including craniofacial muscles, during embryogenesis, and its absence may impair palate formation.ConclusionsWe describe a new form of hereditary cleft palate in Limousine cattle. We identified two fully linked and deleterious mutations, ultimately leading to the loss-of-function of the MYH3 protein. The mutations were included on the Illumina EuroG10k v8 and EuroGMD v1 SNP chips and are used to set up a reliable eradication strategy in the French Limousine breed.