Search Results (9)

Background: Very-long-chain acyl-CoA dehydrogenase deficiency (VLCADD) is caused by biallelic pathogenic variants in ACADVL (acyl-CoA dehydrogenase very-long-chain), leading to impaired fatty acid oxidation and the accumulation of long-chain acylcarnitine. We report a single case of a two-year-old girl, whose neonatal metabolic screening revealed an acylcarnitine profile suggestive of VLCADD, with residual enzymatic activity of 19.8%. Methods: We performed ACADVL whole-gene sequencing. We then carried out an in silico analysis of the potential effects of the variants with dedicated tools, assessing splicing, RNA structure, RNA binding factors, and protein structure. We also conducted gene expression analysis. Results: Genetic testing identified her as compound heterozygous for the pathogenic ACADVL variant (NM_000018.3):c.848T>C, inherited from her mother, and for the two paternal variants, c.-64T>C in the basal promoter and c.957G>A, a synonymous substitution in exon 10. Gene expression analysis revealed reduced ACADVL mRNA levels in the proband’s blood cells but without abnormal isoform production. A decreased expression of the paternal allele carrying the 957A was also observed. Despite this significant reduction in mRNA levels, the underlying mechanism remains unclear. Conclusions: Although currently healthy, due to the VLCAD residual activity within the range associated with the mild form of the disease, the child might be at potential risk for metabolic decompensation or late-onset VLCADD. Our results indicated an allelic imbalance in mRNA expression and c.957G>A is identified as a hypomorphic allele. This suggests that deep ACADVL sequencing is a valuable tool for correlating genetic variants with enzymatic activity levels. Full article

Background and Objectives: Canakinumab, a human recombinant monoclonal antibody against interleukin-1ß (IL-1ß), is indicated for the treatment of selected autoinflammatory periodic fever syndromes and rheumatic diseases. Data on its use during pregnancy remain limited and all are primarily derived from case reports. Although animal studies indicate no evidence of reproductive toxicity, the risk to the fetus or mother remains unknown. This study aims to provide more findings about this important topic. Methods: A retrospective analysis was conducted on three patients followed and treated in the National Center for Periodic Fever Syndromes. Although due to the small sample size, no general conclusions regarding the safety of canakinumab during pregnancy can be drawn. Results: Three maternal-exposed pregnancies were assessed, with no paternal exposure. Diagnoses included mevalonate kinase deficiency, familiar Mediterranean fever and TNF-receptor-associated periodic syndrome. All mothers were treated with canakinumab, and two of those continued the canakinumab treatment during the whole course of pregnancy. The diseases remained under full control during pregnancy, enabling conception in two cases where attempts prior to treatment were unsuccessful. The therapy led to disease control, a reduction in inflammation and subsequently successful conception. One patient underwent IVF repeatedly. All pregnancies resulted in three healthy infants, with no reported miscarriages during the canakinumab-exposed pregnancies, no complications during pregnancies and no serious infections in the newborns. The children had normal development, without any developmental delays or chronic illnesses. Conclusions: The current data, including our findings, indicate no harmful effects of canakinumab during pregnancy. However, because of the scarcity of data, the use of canakinumab during pregnancy should be carefully managed, and women who want to become pregnant should continue treatment only after a thorough benefit–risk evaluation. Full article

Background: Prader–Willi syndrome (PWS) is a rare genetic disorder mapping to the imprinted 15q11-13 locus, specifically at the paternally expressed snord116 region, which has been implicated in controlling epigenetic mechanisms. Some aspects of the PWS-related clinical phenotype, such as the high mortality rate in adulthood, might be attributed to accelerated epigenetic ageing. Objectives: The aim of the present case–control study was to evaluate epigenetic age, age acceleration, vascular age (VA), and vascular ageing in adults with PWS (n = 24; F/M = 11/13; age = 36.8 [26.6; 45.3] years; body mass index, BMI = 36.8 [33.9; 44.8] kg/m²), compared with a sex- and age-matched group of subjects with essential obesity (EOB) (n = 36; F/M = 19/17; age = 43.4 [30.6; 49.5] years; BMI = 44.8 [41.2; 51.7] kg/m²). Results: In subjects with PWS, there was a younger epigenetic age and a lower age acceleration than in subjects with EOB. No differences were found between VA and vascular ageing in the two groups. Epigenetic age was associated with chronological age and VA within each group. For each group, no relevant associations of epigenetic age or age acceleration with demographic, biochemical, and clinical parameters were found. When considering individuals with PWS, there were no associations of epigenetic age with growth hormone (GH) deficiency, duration of hormone replacement therapy, and plasma levels of insulin-like growth factor 1 (IGF-1). Conclusions: The hypothesis of accelerated epigenetic ageing in PWS should be rejected. Additionally, considering the existence of a SNORD116-dependent epigenetic dysregulation in PWS, the results of the present study might be misleading, since an epigenetics-based approach was used to measure ageing. Full article

Prader–Willi Syndrome (PWS) is a rare genetic disorder typically characterized by decreased social interaction, hyperphagia, poor behavioral control and temper tantrums, together with a high risk of morbid obesity unless food intake is controlled. The genetic defects that cause PWS include paternal 15q deletion (estimated in 60% of cases), chromosome 15 maternal uniparental disomy (UPD) (estimated in 35% of cases) and imprinting defects and translocations. Several studies indicate an oxytocin deficiency in PWS. Oxytocin is a hypothalamic nonapeptide with receptors located in the brain and in various other tissues in the body. It acts as a neuropeptide in several brain areas of great importance for behavioral and metabolic effects, as well as a neurohypophyseal hormone released into the circulation. Oxytocin in both rats and humans has strong and long-lasting behavioral and metabolic effects. Thus, an oxytocin deficiency might be involved in several of the behavioral and metabolic symptoms characterizing PWS. Treatment with oxytocin has, in some studies, shown improvement in psycho-social behavior and hyperphagia in individuals with PWS. This review focus on the behavioral and metabolic effects of oxytocin, the symptoms of a potential oxytocin deficiency in PWS and the effects of oxytocin treatment. Full article

In the realm of DNA testing with legal implications, the reliability and precision of genetic markers play a pivotal role in confirming or negating paternity claims. This study aimed to assess the potential utility of human leukocyte antigen (HLA) gene polymorphism through massively parallel sequencing (MPS) technology as robust forensic markers for parentage testing involving genetic deficiencies. It sought to redefine the significance of HLA genes in this context. Data on autosomal short tandem repeat (aSTR) mutational events across 18 paternity cases involving 16 commonly employed microsatellite loci were presented. In instances where traditional aSTR analysis failed to establish statistical certainty, kinship determination was pursued via HLA genotyping, encompassing the amplification of 17 linked HLA loci. Within the framework of this investigation, phase-resolved genotypes for HLA genes were meticulously generated, resulting in the definition of 34 inherited HLA haplotypes. An impressive total of 274 unique HLA alleles, which were classified at either the field 3 or 4 level, were identified, including the discovery of four novel HLA alleles. Likelihood ratio (LR) values, which indicated the likelihood of the observed data under a true biological relationship versus no relationship, were subsequently calculated. The analysis of the LR values demonstrated that the HLA genes significantly enhanced kinship determination compared with the aSTR analysis. Combining LR values from aSTR markers and HLA loci yielded conclusive outcomes in duo paternity cases, showcasing the potential of HLA genes and MPS technology for deeper insights and diversity in genetic testing. Comprehensive reference databases and high-resolution HLA typing across diverse populations are essential. Reintegrating HLA alleles into forensic identification complements existing markers, creating a potent method for future forensic analysis. Full article

Head and neck paragangliomas (HNPGLs) are rare neuroendocrine neoplasms derived from the parasympathetic paraganglia of the head and neck. At least 30% of HNPGLs are linked to germline mutations, predominantly in SDHx genes. In this study, we analyzed an extended cohort of Russian patients with HNPGLs using whole-exome sequencing and found a highly frequent missense variant p.H102R in the SDHD gene. We determined this variant in 34% of the SDHD mutation carriers. This variant was associated with somatic loss of the gene wild-type allele. Data from the B allele frequency method and microsatellite and microdeletion analysis indicated evident LOH at the 11p15.5 region and potential loss of the whole of chromosome 11. We found hypermethylation of H19-DMR in all tumors, whereas differential methylation of KvDMR was mostly retained. These findings do not support the paternal transmission of SDHD:p.H102R but are in agreement with the Hensen model. Using targeted sequencing, we also studied the variant frequency in a control cohort; we found SDHD:p.H102R in 1.9% of cases, allowing us to classify this variant as pathogenic. The immunohistochemistry of SDHB showed that the SDHD:p.H102R mutation, even in combination with wild-type allele loss, does not always lead to SDH deficiency. The obtained results demonstrate the frequent variant associated with HNPGLs in a Russian population and support its pathogenicity. Our findings help with understanding the mechanism of tumorigenesis and are also important for the development of cost-effective genetic screening programs. Full article

Colorectal cancer (CRC) in adolescents and young adults (AYA) is very rare. Known predisposition syndromes include Lynch syndrome (LS) due to highly penetrant MLH1 and MSH2 alleles, familial adenomatous polyposis (FAP), constitutional mismatch-repair deficiency (CMMRD), and polymerase proofreading-associated polyposis (PPAP). Yet, 60% of AYA-CRC cases remain unexplained. In two teenage siblings with multiple adenomas and CRC, we identified a maternally inherited heterozygous PMS2 exon 12 deletion, NM_000535.7:c.2007-786_2174+493del1447, and a paternally inherited POLD1 variant, NP_002682.2:p.Asp316Asn. Comprehensive molecular tumor analysis revealed ultra-mutation (>100 Mut/Mb) and a large contribution of COSMIC signature SBS20 in both siblings’ CRCs, confirming their predisposition to AYA-CRC results from a high propensity for somatic MMR deficiency (MMRd) compounded by a constitutional Pol δ proofreading defect. COSMIC signature SBS20 as well as SBS26 in the index patient’s CRC were associated with an early mutation burst, suggesting MMRd was an early event in tumorigenesis. The somatic second hits in PMS2 were through loss of heterozygosity (LOH) in both tumors, suggesting PPd-independent acquisition of MMRd. Taken together, these patients represent the first cases of cancer predisposition due to heterozygous variants in PMS2 and POLD1. Analysis of their CRCs supports that POLD1-mutated tumors acquire hypermutation only with concurrent MMRd. Full article

A civil paternity investigation involving the parents of the deceased alleged father in order to establish a family relationship is presented. On the basis of the 23 autosomal short tandem repeat (aSTR) genotyping results, conclusive proof of paternity was not achieved, as the probability of paternity (W) was calculated to 0.99988. Additional genetic data of 17 classical and non-classical human leukocyte alleles (HLA) typing by next-generation sequencing (NGS) at a high-resolution level supported the hypothesis of grandpaternity over the hypothesis of coincidental paternal obligate allele (POA) sharing (total W_aSTR&HLA = 0.9999998). The present study demonstrates the utility of 17 HLA genetic markers-typing in the solution of deficiency cases of disputed parentage. Full article

Two siblings from a Mexican family who carried lethal Raine syndrome are presented. A newborn term male (case 1) and his 21 gestational week brother (case 2), with a similar osteosclerotic pattern: generalized osteosclerosis, which is more evident in facial bones and cranial base. Prenatal findings at 21 weeks and histopathological features for case 2 are described. A novel combination of biallelic FAM20C pathogenic variants were detected, a maternal cytosine duplication at position 456 and a paternal deletion of a cytosine in position 474 in exon 1, which change the reading frame with a premature termination at codon 207 and 185 respectively. These changes are in concordance with a negative detection of the protein in liver and kidney as shown in case 2. Necropsy showed absence of pancreatic Langerhans Islets, which are reported here for the first time. Corpus callosum absence is added to the few reported cases of brain defects in Raine syndrome. This report shows two new FAM20C variants not described previously, and negative protein detection in the liver and the kidney. We highlight that lethal Raine syndrome is well defined as early as 21 weeks, including mineralization defects and craniofacial features. Pancreas and brain defects found here in FAM20C deficiency extend the functional spectrum of this protein to previously unknown organs. Full article