RESUMO
Primrose syndrome is characterized by variable intellectual deficiency, behavior disorders, facial features with macrocephaly, and a progressive phenotype with hearing loss and ectopic calcifications, distal muscle wasting, and contractures. In 2014, ZBTB20 variants were identified as responsible for this syndrome. Indeed, ZBTB20 plays an important role in cognition, memory, learning processes, and has a transcription repressive effect on numerous genes. A more severe phenotype was discussed in patients with missense single nucleotide variants than in those with large deletions. Here, we report on the clinical and molecular results of 14 patients: 6 carrying ZBTB20 missense SNVs, 1 carrying an early truncating indel, and 7 carrying 3q13.31 deletions, recruited through the AnDDI-Rares network. We compared their phenotypes and reviewed the data of the literature, in order to establish more powerful phenotype-genotype correlations. All 57 patients presented mild-to-severe ID and/or a psychomotor delay. Facial features were similar with macrocephaly, prominent forehead, downslanting palpebral fissures, ptosis, and large ears. Hearing loss was far more frequent in patients with missense SNVs (p = 0.002), ectopic calcification, progressive muscular wasting, and contractures were observed only in patients with missense SNVs (p nonsignificant). Corpus callosum dysgenesis (p = 0.00004), hypothyroidism (p = 0.047), and diabetes were also more frequent in this group. However, the median age was 9.4 years in patients with deletions and truncating variant compared with 15.1 years in those with missense SNVs. Longer follow-up will be necessary to determine whether the phenotype of patients with deletions is also progressive.
Assuntos
Anormalidades Múltiplas/genética , Calcinose/genética , Otopatias/genética , Deficiência Intelectual/genética , Atrofia Muscular/genética , Proteínas do Tecido Nervoso/genética , Fenótipo , Fatores de Transcrição/genética , Anormalidades Múltiplas/patologia , Adolescente , Calcinose/patologia , Criança , Pré-Escolar , Deleção Cromossômica , Cromossomos Humanos Par 3/genética , Corpo Caloso/diagnóstico por imagem , Otopatias/patologia , Humanos , Deficiência Intelectual/patologia , Atrofia Muscular/patologia , Mutação de Sentido IncorretoRESUMO
Obesity is a common but highly, clinically, and genetically heterogeneous disease. Deletion of the terminal region of the short arm of chromosome 2 is rare and has been reported in about 13 patients in the literature often associated with a Prader-Willi-like phenotype. We report on five unrelated patients with 2p25 deletion of paternal origin presenting with early-onset obesity, hyperphagia, intellectual deficiency, and behavioural difficulties. Among these patients, three had de novo pure 2pter deletions, one presented with a paternal derivative der(2)t(2;15)(p25.3;q26) with deletion in the 2pter region and the last patient presented with an interstitial 2p25 deletion. The size of the deletions was characterized by SNP array or array-CGH and was confirmed by fluorescence in situ hybridization (FISH) studies. Four patients shared a 2p25.3 deletion with a minimal critical region estimated at 1.97 Mb and encompassing seven genes, namely SH3HYL1, ACP1, TMEMI8, SNTG2, TPO, PXDN, and MYT1L genes. The fifth patient had a smaller interstitial deletion encompassing the TPO, PXDN, and MYT1L genes. Paternal origin of the deletion was determined by genotyping using microsatellite markers. Analysis of the genes encompassed in the deleted region led us to speculate that the ACP1, TMEM18, and/or MYT1L genes might be involved in early-onset obesity. In addition, intellectual deficiency and behavioural troubles can be explained by the heterozygous loss of the SNTG2 and MYT1L genes. Finally, we discuss the parent-of-origin of the deletion.
Assuntos
Cromossomos Humanos Par 2/genética , Proteínas de Membrana/genética , Proteínas do Tecido Nervoso/genética , Obesidade/genética , Proteínas Tirosina Fosfatases/genética , Proteínas Proto-Oncogênicas/genética , Deleção de Sequência , Fatores de Transcrição/genética , Criança , Pré-Escolar , Hibridização Genômica Comparativa , Feminino , Estudo de Associação Genômica Ampla , Genótipo , Humanos , Hibridização in Situ Fluorescente , Masculino , Obesidade/complicações , Obesidade/diagnóstico , Fenótipo , Polimorfismo de Nucleotídeo Único , Síndrome de Prader-Willi/complicações , Síndrome de Prader-Willi/genética , Análise de Sequência de DNARESUMO
We report the association of aphallia, with imperforate anus, bilateral renal dysplasia and complete right lung agenesis in a fetus born of non-consanguineous parents. No maternal diabetes was present. The multiple mesodermal anomalies present in this male fetus, with a severe form of Uro-Rectal-Septum Malformation Sequence associated with unilateral lung agenesis, and rib segmentation anomaly is consistent with an extended defect of blastogenesis, with apparent common timing of the malformations around the 5th to 7th weeks of gestation.