Deleterious Alterations Research Articles

Inactivation of the CDKN2A Tumor-Suppressor Gene by Deletion or Methylation Is Common at Diagnosis in Follicular Lymphoma and Associated with Poor Clinical Outcome

Follicular lymphoma, the most common indolent lymphoma, is clinically heterogeneous. CDKN2A encodes the tumor suppressors p16(INK4a) and p14(ARF) and frequently suffers deleterious alterations in cancer. We investigated the hypothesis that deletion or hypermethylation of CDKN2A might identify follicular lymphoma cases with distinct clinical or pathologic features potentially amenable to tailored clinical management. Deletion of CDKN2A was detected in pretreatment biopsy specimens using a single nucleotide polymorphism-based approach or endpoint PCR, and methylation of CpG elements in CDKN2A was quantified by methylation-specific PCR. Correlations between CDKN2A status and pathologic or clinical characteristics, including overall survival (OS), were investigated in 106 cases using standard statistical methods. Deletion of CDKN2A was detected in 9 of 111 samples (8%) and methylation was detectable in 22 of 113 (19%). CDKN2A was either deleted or methylated in 29 of 106 cases (27%) and this status was associated with inferior OS especially among patients treated with rituximab (P = 0.004). CDKN2A deletion or methylation was associated with more advanced age (P = 0.012) and normal hemoglobin (P = 0.05) but not with sex, FLIPI score, ECOG stage, LDH, performance status, number of involved nodal sites, B symptoms, histologic grade, the presence of a component of diffuse large B-cell lymphoma, proliferation index, or other pathologic factors. Our results show that deletion or methylation of CDKN2A is relatively common in pretreatment follicular lymphoma biopsy specimens and defines a group of cases associated with reduced survival in the rituximab era presumably on the basis of more aggressive disease biology.

Caffeinated and decaffeinated instant coffee consumption partially reverses high-fat diet-induced metabolic alterations in mice

Epidemiological data has associated coffee consumption with a lower prevalence of type 2 diabetes, metabolic syndrome and chronic liver disease. However, the mechanisms and coffee substances responsible for these effects remain unclear. In the present study, mice received caffeinated or decaffeinated instant coffee ad libitum during a two week period after inducing obesity by introducing a high-fat diet over a 10week period. Body weight, glucose homeostasis, and liver and visceral adipose tissue inflammation were assessed. In addition, AKT signaling, the fatty acid profile and liver histopathological analyses were performed. Ingestion of caffeinated or decaffeinated coffee for 2weeks resulted in reductions in glucose and insulin blood levels, and insulin tolerance was improved without reductions in final body weight or adiposity. Only caffeinated coffee modified the adipokine profile in visceral adipose tissue, resulting in a restoration of adiponectin levels. However, deleterious liver alterations, which manifested as reductions in steatosis, inhibition of iNOS expression and restoration of insulin inducing-AKT phosphorylation, were reversed by the ingestion of both caffeinated and decaffeinated coffee. Serum AST and ALT levels were also improved in mice after coffee ingestion, while the fatty acid profile in the liver and the cytokine profiles in adipose and liver tissues were not altered by coffee ingestion. Thus, instant coffee consumption reverses obesity-induced alterations in mice, and our results corroborate those of epidemiological studies that associated coffee consumption with a lower prevalence of obesity-related pathologies.

Next-generation sequencing for the diagnosis of hereditary breast and ovarian cancer using genomic capture targeting multiple candidate genes

To optimize the molecular diagnosis of hereditary breast and ovarian cancer (HBOC), we developed a next-generation sequencing (NGS)-based screening based on the capture of a panel of genes involved, or suspected to be involved in HBOC, on pooling of indexed DNA and on paired-end sequencing in an Illumina GAIIx platform, followed by confirmation by Sanger sequencing or MLPA/QMPSF. The bioinformatic pipeline included CASAVA, NextGENe, CNVseq and Alamut-HT. We validated this procedure by the analysis of 59 patients' DNAs harbouring SNVs, indels or large genomic rearrangements of BRCA1 or BRCA2. We also conducted a blind study in 168 patients comparing NGS versus Sanger sequencing or MLPA analyses of BRCA1 and BRCA2. All mutations detected by conventional procedures were detected by NGS. We then screened, using three different versions of the capture set, a large series of 708 consecutive patients. We detected in these patients 69 germline deleterious alterations within BRCA1 and BRCA2, and 4 TP53 mutations in 468 patients also tested for this gene. We also found 36 variations inducing either a premature codon stop or a splicing defect among other genes: 5/708 in CHEK2, 3/708 in RAD51C, 1/708 in RAD50, 7/708 in PALB2, 3/708 in MRE11A, 5/708 in ATM, 3/708 in NBS1, 1/708 in CDH1, 3/468 in MSH2, 2/468 in PMS2, 1/708 in BARD1, 1/468 in PMS1 and 1/468 in MLH3. These results demonstrate the efficiency of NGS in performing molecular diagnosis of HBOC. Detection of mutations within other genes than BRCA1 and BRCA2 highlights the genetic heterogeneity of HBOC.

Clinical Characteristics of Ovarian Cancer Classified by BRCA1, BRCA2 and RAD51C Status

We evaluated homologous recombination deficient (HRD) phenotypes in epithelial ovarian cancer (EOC) considering BRCA1, BRCA2, and RAD51C in a large well-annotated patient set. We evaluated EOC patients for germline deleterious mutations (n = 899), somatic mutations (n = 279) and epigenetic alterations (n = 482) in these genes using NGS and genome-wide methylation arrays. Deleterious germline mutations were identified in 32 (3.6%) patients for BRCA1, in 28 (3.1%) for BRCA2 and in 26 (2.9%) for RAD51C. Ten somatically sequenced patients had deleterious alterations, six (2.1%) in BRCA1 and four (1.4%) in BRCA2. Fifty two patients (10.8%) had methylated BRCA1 or RAD51C. HRD patients with germline or somatic alterations in any gene were more likely to be high grade serous, have an earlier diagnosis age and have ovarian and/or breast cancer family history. The HRD phenotype was most common in high grade serous EOC. Identification of EOC patients with an HRD phenotype may help tailor specific therapies.

Protective Effect of Melatonin on Kainic Acid Induced-Liver Damage and Immune Modulatory Cytokines

Liver toxicity occurs when liver develops inflammation due to exposure to several toxic substances. The study was aimed to assess the liver damage induced by kainic acid and subsequently protective role of exogenous melatonin against the liver toxicity. Interestingly, kainic acid caused severe liver damage as evident from deleterious alterations in liver histology, increased lipid peroxide levels, decrease in the activities of liver anti-oxidant enzymes, DNA damage (adduct formation and sequence alterations), increased expression of cytokines like monocyte chemoattractant protein-1, interleukin 6, interferon γ and decreased expression of interleukin 10. These changes were normalized by melatonin (0.5-1.0 mM, (in vitro) or 10–20 mg/kg, (in vivo)). The study included assessment of the expression of immune modulatory cytokine mediators using real time PCR in both in vitro and in vivo conditions in the mouse liver. DNA damage was also studied. Various oxidative stress parameters and liver histopathology was also evaluated. Melatonin’s anti-kainic acid toxicity could be brought about by counter acting the influence of kainic acid on the levels of the cytokines, immune reactions and free radical production. This work suggests that melatonin receptors present could be mediate the hepatoprotective actions of melatonin therapy.

Negative neuroplasticity in chronic traumatic brain injury and implications for neurorehabilitation.

Based on growing findings of brain volume loss and deleterious white matter alterations during the chronic stages of injury, researchers posit that moderate-severe traumatic brain injury (TBI) may act to “age” the brain by reducing reserve capacity and inducing neurodegeneration. Evidence that these changes correlate with poorer cognitive and functional outcomes corroborates this progressive characterization of chronic TBI. Borrowing from a framework developed to explain cognitive aging (Mahncke et al., Progress in Brain Research, 157, 81–109, 2006a; Mahncke et al., Proceedings of the National Academy of Sciences of the United States of America, 103(33), 12523–12528, 2006b), we suggest here that environmental factors (specifically environmental impoverishment and cognitive disuse) contribute to a downward spiral of negative neuroplastic change that may modulate the brain changes described above. In this context, we review new literature supporting the original aging framework, and its extrapolation to chronic TBI. We conclude that negative neuroplasticity may be one of the mechanisms underlying cognitive and neural decline in chronic TBI, but that there are a number of points of intervention that would permit mitigation of this decline and better long-term clinical outcomes.

Regular exercise prevents non-cognitive disturbances in a rat model of Alzheimer's disease

Previously, we reported that in a rat model of sporadic Alzheimer's disease (AD) generated by exogenous administration of Aβ₁₋₄₂ (250 pmol/d for 2 wk) via mini-osmotic pump, the animals exhibited learning and memory impairment, which could be attributed to the deleterious alterations in the levels of cognition-related signalling molecules. We showed that 4 wk of treadmill exercise totally prevented these impairments. Here, we evaluated the effect of exercise on non-cognitive function and basal synaptic transmission in the Cornu Ammonis 1 (CA1) area using the same AD model. Our results indicated that the anxiety behaviour of Aβ-treated rats was prevented by 4 wk of treadmill exercise. Exercised/Aβ-infused rats spent a longer time in the centre area of the open field (OF), elevated plus maze (EPM) paradigms and the light area of the light-dark (LD) box, which were similar to those of control and exercise rats. Furthermore, under basal conditions the aberrant up-regulation of calcineurin (PP2B) and reduction of phosphorylated Ca²⁺/calmodulin dependent protein kinase II (p-CaMKII) levels induced by AD-like pathology were normalised by the exercise regimen. We conclude that regular exercise may exert beneficial effects on both cognitive and non-cognitive functions in this AD model.

A Novel Large In-Frame Deletion within the CACNA1F Gene Associates with a Cone-Rod Dystrophy 3-Like Phenotype

Cone-rod dystrophies (CORDs) represent a heterogeneous group of monogenic diseases leading to early impairment of vision. The majority of CORD entities show autosomal modes of inheritance and X-linked traits are comparably rare. So far, three X-chromosomal entities were reported (CORDX1, -X2 and -X3). In this study, we analysed a large family of German origin with solely affected males over three generations showing a CORDX-like phenotype. Due to the heterogeneity of cone-rod dystrophies, we performed a combined linkage and X-exome sequencing approach and identified a novel large intragenic in-frame deletion encompassing exons 18 to 26 within the CACNA1F gene. CACNA1F is described causative for CORDX3 in a single family originating from Finland and alterations in this gene have not yet been reported in other CORDX pedigrees. Our data independently confirm CACNA1F as the causative gene for CORDX3-like phenotypes and detailed clinical characterization of the family expands the knowledge about the phenotypic spectrum of deleterious CACNA1F alterations.

Medial Meniscal Root Avulsion: A Biomechanical Comparison of Four Different Repair Constructs.

A locking loop stitch used to repair medial meniscal root avulsions proved significantly stronger in time-zero pullout strength than three other suture consstructs. Medial meniscal root avulsion may lead to a deleterious alteration of medial compartment loading and increased risk of cartilage degeneration. Repair of this injury has been proposed to restore normal biomechanics of the knee. The Purpose of this study was to evaluate the time-zero pullout strength of four different constructs used to repair medial meniscal root avulsions. (1) No meniscal root repair technique will be as biomechanically strong as the intact meniscus. (2) A looped suture construct will resist greater loads than simple sutures. Sixty fresh-frozen cadaveric knees with a mean age of 74 years were used for this study. Each knee was dissected to isolate the attachment of the posterior root of the medial meniscus to the tibial plateau. An Instron machine with custom-designed clamp was used to avulse the intact posterior meniscal root in 12 Control specimens. An additional 48 specimens were tested after transection of the native meniscal root to evaluate the pullout strength of four different repair constructs using #0 FiberWire suture secured to a screw through a trans-tibial tunnel: a Single Suture (n=12), Double Suture (n=12), Loop Stitch (n=12), and a novel Locking Loop Stitch (n=12). Analysis of variance was used to compare pullout strength of all groups with pairwise between-group differences assessed using Tukey’s-adjustment for multiple testing. Repair failure occurred most commonly by suture pullout in 94% of the specimens in the repair groups. For the Controls, failure occurred most commonly at the meniscus-clamp interface. Failure strength was highest for the Control group (mean: 359.5 N + 168 N), followed in descending order by the Locking Loop Stitch (191.4 N + 45.1 N), Loop Stitch (119.6 + 55.0 N), Double Suture (96.2 N + 51.4 N), and Single Suture (58.2 N + 29.6). The Control group was significantly stronger (p<0.0001) than three of the experimental groups (Single Suture, Double Suture, and Loop Stitch) but not the Locking Loop Stitch (p=0.056). The Locking Loop Stitch was significantly stronger than the Single Suture (p<0.0001) and Double Suture (p=0.002) and trended toward significance compared to the Loop Stitch (p=0.06). Age and gender had no effect on pullout strength. The results of this study showed that the novel Locking Loop Stitch provided pullout strength that most closely approximated the strength of the native meniscal root in addition to being significantly stronger than commonly used repair methods. The Locking Loop may be the preferred method for repair of medial meniscal root avulsions.

Serotonin (5HT) expression in rat pups treated with high-tryptophan diet during fetal and early postnatal development

Serotonin (5HT) is a neurotransmitter synthesized in serotonergic neurons of the central nervous system and in the enterochromaffin cells of the gastrointestinal tract. 5HT regulates growth and maturation of some cerebral regions in the developing brain as well as the secretion of pituitary growth hormone. This hormone is necessary for development and growth through the stimulation of insulin-like growth factor synthesis. The precursor of 5HT, tryptophan (Trp), is an essential amino acid, since the human organism is unable to synthesize it and it is assumed only through diet. The aim of our study was to analyze how a high-tryptophan diet in pregnant rats affects growth and survival of pups until weaning. We monitored the number and weight of pups until weaning. Then, we detected serotonin and growth hormone levels in whole blood by ELISA of surviving pups at the end of the lactation period. We also analyzed by means of immunohistochemistry and Western blot the expression of serotonin in rat gastric tissue and the morphological structure of skeletal muscle tissue of both control and experimental pups. Hyperserotonemia and very low levels of growth hormone were detected in experimental pups compared to controls. Immunohistochemistry demonstrated a strong serotonin expression in stomach samples confirming that a high intake of tryptophan increases the production of serotonin in enterochromaffin cells, thereby resulting in hyperserotonemia in pups. These data were also strengthened by Western blot analysis. Histological alterations of skeletal muscle fibers in experimental pups were found and showed that in experimental samples the muscle tissue demonstrated deleterious alterations, being less developed and defined. Our data suggest that a high-tryptophan diet in pregnant rats induces hyperserotonemia in the fetus. Hyperserotonemia results in an excess of serotonin in the brain where it has a negative influence on development of serotonergic neurons and consequently on growth hormone production.

Keloids and non-diabetic kidney disease: Similarities and the APOL1–MYH9 haplotype as a possible genetic link

Keloids and non-diabetic kidney disease are both fibrotic processes that disproportionately affect persons of African descent. Despite similarities in these conditions, the authors identified no studies to date investigating a shared genetic etiology. MYH9 and APOL1 are in linkage disequilibrium and have both been associated with non-diabetic kidney disease. MYH9 codes for a non-muscle myosin that is involved in cell adhesion and locomotion and is known to be overexpressed in keloids. Variations in APOL1 confer resistance to subspecies of Trypanosoma brucei, which may explain why otherwise deleterious genetic alterations in this haplotype could have gained prominence. We feel that the pathophysiological and epidemiological overlap between keloids and non-diabetic kidney disease support a common genetic origin and further investigation into keloids and the MYH9–APOL1 haplotype and keloids is warranted. Furthermore, we feel this haplotype might offer insight into thrombosis, stroke and other conditions that disproportionately affect persons of African descent.

Accumulation, histopathology and immunotoxicological effects of waterborne cadmium on gilthead seabream (Sparus aurata)

Studies in fish have demonstrated that Cd-exposure produce skeletal deformities and alterations in tissue morphology, enzyme activities, stress response, ion regulation and immune response. In the present work, gilthead seabream (Sparus aurata) specimens were exposed to waterborne Cd (5 μM CdCl2 or 1 mg L−1) for 2, 10 or 30 days. Organo-somatic changes, Cd accumulation, liver histology and humoral and cellular immune responses were determined. Results showed that exposure of seabream specimens to Cd induced no alterations on spleen and liver organo-somatic indexes whilst produced progressive deleterious morphological alterations in liver and exocrine pancreas that correlated with the hepatic Cd-accumulation. Regarding the immunotoxicological potential, strikingly, Cd-exposure produced a reduction in the serum complement activity and leucocyte respiratory burst to a significant extent after 10 and 30 days whilst the serum peroxidase activity and leucocyte phagocytosis were increased at different sampling times. On the other hand, serum IgM levels and leucocyte peroxidase activity resulted unaltered. The present results seem to indicate that seabream exposed to Cd in the present conditions suffer toxicity.

Medial Meniscal Root Avulsion: A Biomechanical Comparison of Four Different Repair Constructs (SS-67)

Medial Meniscal Root Avulsion: A Biomechanical Comparison of Four Different Repair Constructs (SS-67)

Treadmill Exercise Prevents Learning and Memory Impairment in Alzheimer’s Disease-Like Pathology

Alzheimer's disease (AD) is a neurodegenerative disorder that is characterized by progressive memory loss. In contrast, accumulating evidence suggests a neuroprotective role of regular exercise in aging associated memory impairment. In this study, we investigated the ability of regular exercise to prevent impairments of short-term memory (STM) and early long-term potentiation (E-LTP) in area CA1 of the hippocampus in a rat model of AD (i.c.v. infusion of 250 pmol/day Aβ1-42 peptides). We utilized behavioral assessment, in vivo electrophysiological recording, and immunoblotting in 4 groups of adult Wistar rats: control, treadmill exercise (Ex), β-amyloid-infused (Aβ), and amyloid-infused/treadmill exercised (Ex/Aβ). Our findings indicated that Aβ rats made significantly more errors in the radial arm water maze (RAWM) compared to all other groups and exhibited suppressed E-LTP in area CA1, which correlated with deleterious alterations in the levels of memory and E-LTP-related signaling molecules including calcineurin (PP2B), brain derivedneurotrophic factor (BDNF) and phosphorylated CaMKII (p-CaMKII). Compared to controls, Ex and Ex/Aβ rats showed a similar behavioral performance and a normal E-LTP with no detrimental changes in the levels of PP2B, BDNF, and p- CaMKII. We conclude that treadmill exercise maybe able to prevent cognitive impairment associated with AD pathology.

Assessment of gadoxetate DCE‐MRI as a biomarker of hepatobiliary transporter inhibition

Drug-induced liver injury (DILI) is a clinically important adverse drug reaction, which prevents the development of many otherwise safe and effective new drugs. Currently, there is a lack of sensitive and specific biomarkers that can be used to predict, assess and manage this toxicity. The aim of this work was to evaluate gadoxetate-enhanced MRI as a potential novel biomarker of hepatobiliary transporter inhibition in the rat. Initially, the volume fraction of extracellular space in the liver was determined using gadopentetate to enable an estimation of the gadoxetate concentration in hepatocytes. Using this information, a compartmental model was developed to characterise the pharmacokinetics of hepatic uptake and biliary excretion of gadoxetate. Subsequently, we explored the impact of an investigational hepatobiliary transporter inhibitor on the parameters of the model in vivo in rats. The investigational hepatobiliary transporter inhibitor reduced both the rate of uptake of gadoxetate into the hepatocyte, k1, and the Michaelis–Menten constant, Vmax, characterising its excretion into bile, whereas KM values for biliary efflux were increased. These effects were dose dependent and correlated with effects on plasma chemistry markers of liver dysfunction, in particular bilirubin and bile acids. These results indicate that gadoxetate-enhanced MRI provides a novel functional biomarker of inhibition of transporter-mediated hepatic uptake and clearance in the rat. Since gadoxetate is used clinically, the technology has the potential to provide a translatable biomarker of drug-induced perturbation of hepatic transporters that may also be useful in humans to explore deleterious functional alterations caused by transporter inhibition. Copyright © 2013 John Wiley & Sons, Ltd.

Protection of Cigarette Smoke‐Induced Lung Injury in Guinea Pigs by Inhalation of Aerosolic All‐Trans Retinoic Acid

Both mainstream (MS) and secondhand (SH) cigarette smoking are known to cause abnormality in lung function. We reported earlier that both MS and SH cigarette smoke exposure to guinea pigs caused lung injury associated with accumulation of retinol. The accumulation of retinol in lung was later found to be associated with a decrease in the levels of retinoic acid implying an abnormality in lung retinoid metabolism and signaling. The objective of the present study was to investigate whether inhalation of aerosolic all‐trans retinoic acid (ATRA) immediately smoke exposure can protect against lung damage. Four weeks old male guinea pig were exposed twice daily for 6 weeks to MS or SH smoke from 3 1R3F cigarettes. The sham control group (SC) received a treatment identical to smoke‐exposed groups but in the absence of cigarettes. Four animals from each group received either aerosolic ATRA (2.78mM) or vehicle twice for 20 min/day after smoke exposure. Morphological analysis of lungs showed deleterious alterations in the morphology of the lungs in both MS and SH groups. ATRA treatment showed significant protection against lung damage; however the protection was more evident in MS than SH groups. The mechanism by which ATRA aerosol protects lung against deleterious effects of cigarette smoke is under investigation. (Supported by NIH grant: 1R03HL095419–01A1).

Prophylactic treatment with melatonin after status epilepticus: Effects on epileptogenesis, neuronal damage, and behavioral changes in a kainate model of temporal lobe epilepsy

Melatonin is a potent antioxidant which showed anticonvulsant activities both in experimental and clinical studies. In the present study, we examined the effect of melatonin treatment (10mg/kg/day, diluted in drinking water, 8weeks) during epileptogenesis on the consequences of a kainate (KA)-induced status epilepticus (SE) in rats. Melatonin increased the latency in the appearance of spontaneous recurrent seizures (SRSs) and decreased their frequency only during the treatment period. The behavioral alterations associated with hyperactivity, depression-like behavior during the light phase, and deficits in hippocampus-dependent working memory were positively affected by melatonin treatment in rats with epilepsy. Melatonin reduced the neuronal damage in the CA1 area of the hippocampus and piriform cortex and recovered the decrease of hippocampal serotonin (5-HT) level in rats with epilepsy. Taken together, long-term melatonin treatment after SE was unable to suppress the development of epileptogenesis. However, it showed a potential in reducing some of the deleterious alterations that develop during the chronic epileptic state in a diurnal phase-dependent mode.

Protective Mechanism of Melatonin on Kainic Acid Induced Immune Modulatory Effect on Lymphocytes Derived from Mouse Spleen

Toxicity occurs when cells develop inflammation due to exposure to several toxic substances. The study was aimed to assess the damage (toxicity) induced by kainic acid on splenic lymphocyte and enriched T lymphocyte under in vitro conditions and the protective role of exogenous melatonin against this damage (toxicity). The study included assessment of inflammatory mechanism by the expression of immune modulatory cytokine mediators using real time PCR. Oxidative stress (reactive oxygen species) and nitrosative stress (reactive nitrogen species) were also studied to determine the free radical production. Interestingly, kainic acid caused severe splenic lymphocytes and enriched T lymphocyte damage which was evident from deleterious alterations in various parameters. Kainic acid treatment (1 mM) resulted in increased mRNA expression of cytokines like tumour necrosis factor-beta, interleukin 6, interleukin 1, interferon gamma, mitogen-activated protein kinase gene-14, inducible nitric oxide synthase and decreased interleukin 10 mRNA expression. Tritiated (3H) Thymidine Incorporation study signifies that kainic acid treatment (1 mM) increased the proliferation of splenic and enriched T lymphocytes. These changes were normalized by exogenous administration of melatonin (0.25-1.0 mM) in combination with kainic acid. Flow Cytometry Analysis using Annexin V apoptosis assay kit revealed an increase in apoptotic and necrosis (double positive cells) in splenic lymphocytes treated with kainic acid alone. However, melatonin treated in combination with kainic acid, showed attenuation to apoptosis and necrosis on splenic lymphocytes. This study depicts that kainic acid induced inflammatory toxicity could be attenuated by exogenous melatonin treatment as evident by the decreased levels of the inflammatory cytokines, immune reactions and free radical production.

Failure to successfully open a chronic total coronary occlusion is associated with preserved global, but impaired regional myocardial function

Background Non-randomized studies have reported a prognostic advantage with percutaneous coronary intervention (PCI) in the treatment of chronic total occlusions (CTO). However failure to cross and successfully open a CTO confers a worse clinical outcome. Quantitative assessment of global left ventricular (LV) function in those with failure to open a CTO has not demonstrated deleterious alterations in cardiac function/remodeling. We hypothesized that more sensitive techniques that assess regional wall motion, such as strain imaging, may identify segments where cardiac function is adversely affected in those with failure to open the CTO. Methods

Spectrum of NIPBL gene mutations in Polish patients with Cornelia de Lange syndrome

Cornelia de Lange syndrome (CdLS) is a rare multi-system genetic disorder characterised by growth and developmental delay, distinctive facial dysmorphism, limb malformations and multiple organ defects. The disease is caused by mutations in genes responsible for the formation and regulation of cohesin complex. About half of the cases result from mutations in the NIPBL gene coding delangin, a protein regulating the initialisation of cohesion. To date, approximately 250 point mutations have been identified in more than 300 CdLS patients worldwide. In the present study, conducted on a group of 64 unrelated Polish CdLS patients, 25 various NIPBL sequence variants, including 22 novel point mutations, were detected. Additionally, large genomic deletions on chromosome 5p13 encompassing the NIPBL gene locus were detected in two patients with the most severe CdLS phenotype. Taken together, 42 % of patients were found to have a deleterious alteration affecting the NIPBL gene, by and large private ones (89 %). The review of the types of mutations found so far in Polish patients, their frequency and correlation with the severity of the observed phenotype shows that Polish CdLS cases do not significantly differ from other populations.