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Summary Objective Copy number variations (CNVs) represent a significant genetic risk for several neurodevelopmental disorders including epilepsy. As knowledge increases, reanalysis of existing data is essential. Reliable estimates of the contribution of CNVs to epilepsies from sizeable populations are not available. Methods We assembled a cohort of 1255 patients with preexisting array comparative genomic hybridization or single nucleotide polymorphism array based CNV data. All patients had “epilepsy plus,” defined as epilepsy with comorbid features, including intellectual disability, psychiatric symptoms, and other neurological and nonneurological features. CNV classification was conducted using a systematic filtering workflow adapted to epilepsy. Results Of 1097 patients remaining after genetic data quality control, 120 individuals (10.9%) carried at least one autosomal CNV classified as pathogenic; 19 individuals (1.7%) carried at least one autosomal CNV classified as possibly pathogenic. Eleven patients (1%) carried more than one (possibly) pathogenic CNV. We identified CNVs covering recently reported (HNRNPU) or emerging (RORB) epilepsy genes, and further delineated the phenotype associated with mutations of these genes. Additional novel epilepsy candidate genes emerge from our study. Comparing phenotypic features of pathogenic CNV carriers to those of noncarriers of pathogenic CNVs, we show that patients with nonneurological comorbidities, especially dysmorphism, were more likely to carry pathogenic CNVs (odds ratio = 4.09, confidence interval = 2.51‐6.68; P = 2.34 × 10−9). Meta‐analysis including data from published control groups showed that the presence or absence of epilepsy did not affect the detected frequency of CNVs. Significance The use of a specifically adapted workflow enabled identification of pathogenic autosomal CNVs in 10.9% of patients with epilepsy plus, which rose to 12.7% when we also considered possibly pathogenic CNVs. Our data indicate that epilepsy with comorbid features should be considered an indication for patients to be selected for a diagnostic algorithm including CNV detection. Collaborative large‐scale CNV reanalysis leads to novel declaration of pathogenicity in unexplained cases and can promote discovery of promising candidate epilepsy genes.

Familial Hemophagocytic lymphohistiocytosis (FHL) is a rare immune deficiency with defective cytotoxic function. The age at onset is usually young and the natural course is rapidly fatal if untreated. A later onset of the disease has been sporadically reported even in adolescents and adults. We report the results of our retrospective data collection of all cases diagnosed with FHL at an age of 18 years or older and enrolled in the Italian Registry of HLH. All cases were diagnosed with FHL based on evidence of genetic defect in one FHL-related gene. A total of 11 patients were diagnosed with FHL. They were 9 males and 2 females, from 10 unrelated families; their age ranged between 18 and 43 years (median, 23 years). Family history was unremarkable in eight families at the time of the diagnosis. Their genetic diagnoses are: FHL2 (n = 6), FHL3 (n = 2), FHL5 (n = 1), XLP1 (n = 2). Clinical, molecular and functional data are described. These data confirm that FHL may present beyond the pediatric age and up to the fifth decade. FHL2 due to perforin defect is the most frequently reported subtype. Adult specialists should consider FHL in the differential diagnosis of patients with cytopenia and liver or central nervous system disorders, especially when a lymphoproliferative disease is suspected but eventually not confirmed. FHL may turn to be fatal within a short time course even in adults. This risk, together with the continuous improvement in the transplant technique, especially in the area of transplant from matched unrelated donor, resulting in reduced treatment related mortality, might suggest a wider use of SCT in this population. Current diagnostic approach allows prompt identification of patients by flow-cytometry screening, then confirmed by the genetic study, and treatment with chemoimmunotherapy followed by stem cell transplantation.

X-linked lymphoproliferative disease 1 (XLP1) is a rare congenital immunodeficiency caused by SH2D1A (Xq25) mutations resulting in lack or dysfunction of SLAM-associated protein adaptor molecule. In XLP1 patients, upon ligand (CD48) engagement, 2B4 delivers inhibitory signals that impair the cytolytic activity of NK (and T) cells. This causes the selective inability to control EBV infections and the occurrence of B-cell lymphomas. Here, we show that in the absence of SLAM-associated protein, co-engagement of 2B4 with different activating receptors, either by antibodies or specific ligands on target cells, inhibits different ITAM-dependent signaling pathways including activating killer Ig-like receptors. In XLP1 NK cells, 2B4 affected both the cytolytic and IFN-γ production capabilities, functions that were restored upon disruption of the 2B4/CD48 interactions. Notably, we provide evidence that 2B4 dysfunction does not affect the activity of DNAM-1 and NKG2D triggering receptors. Thus, while CD48(+) B-EBV and lymphoma B cells devoid of NKG2D and DNAM-1 ligands were resistant to lysis, the preferential usage of these receptors allowed XLP1 NK cells to kill lymphomas that expressed sufficient amounts of the specific ligands. The study sheds new light on the XLP1 immunological defect and on the cross-talk of inhibitory 2B4 with triggering NK (and T) receptors.

Familial Hemophagocytic lymphohistiocytosis (FHL) is a rare immune deficiency with defective cytotoxic function. The age at onset is usually young and the natural course is rapidly fatal if untreated. A later onset of the disease has been sporadically reported even in adolescents and adults. We report the results of our retrospective data collection of all cases diagnosed with FHL at an age of 18 years or older and enrolled in the Italian Registry of HLH. All cases were diagnosed with FHL based on evidence of genetic defect in one FHL-related gene. A total of 11 patients were diagnosed with FHL. They were 9 males and 2 females, from 10 unrelated families; their age ranged between 18 and 43 years (median, 23 years). Family history was unremarkable in eight families at the time of the diagnosis. Their genetic diagnoses are: FHL2 (n = 6), FHL3 (n = 2), FHL5 (n = 1), XLP1 (n = 2). Clinical, molecular and functional data are described. These data confirm that FHL may present beyond the pediatric age and up to the fifth decade. FHL2 due to perforin defect is the most frequently reported subtype. Adult specialists should consider FHL in the differential diagnosis of patients with cytopenia and liver or central nervous system disorders, especially when a lymphoproliferative disease is suspected but eventually not confirmed. FHL may turn to be fatal within a short time course even in adults. This risk, together with the continuous improvement in the transplant technique, especially in the area of transplant from matched unrelated donor, resulting in reduced treatment related mortality, might suggest a wider use of SCT in this population. Current diagnostic approach allows prompt identification of patients by flow-cytometry screening, then confirmed by the genetic study, and treatment with chemo-immunotherapy followed by stem cell transplantation.

Assignment tests based on multilocus genotypes are becoming increasingly important to certify quality and origin of livestock products and assure food safety and authenticity. The purpose of this study was to determine the potential of microsatellites (STR) for determining the breed origin of beef products among cattle breeds present in the market. We typed 19 STR in 269 animals from 4 cattle breeds. Based on Wright's F-statistics, 4 loci were discarded, and the remaining 15 loci (FIT = 0.101, FST = 0.089, and FIS = 0.013) were used to compute the likelihood that each multilocus genotype of the total sample was drawn from its true breed instead of another breed. To avoid occurrence of zero likelihood when one or more alleles were missing from a tested breed, sample allele frequencies were estimated assuming uniform prior distributions. Log-likelihood ratio [log(LR)] distributions of the individual assignments were determined for all possible breed contrasts, and their means and SD were used to infer the true-positive and false-positive rates at several values of the log(LR). The posterior probability that the animals of a presumed breed were actually drawn from that breed instead of any another breed was then calculated. Given an observed value of log(LR)0 and assuming equal priors, these probabilities were99.5% in 10 of 12 possible breed contrasts. For the 2 most closely related breeds (FST = 0.041), this probability was 96.3%, and the probability of excluding the origin of an animal from an alleged breed when it was actually derived from another breed was similar.