Susceptibility to Heart Defects in Down Syndrome Is Associated with Single Nucleotide Polymorphisms in HAS 21 Interferon Receptor Cluster and VEGFA Genes.

BACKGROUND: Congenital heart defects (CHDs) are present in about 40-60% of newborns with Down syndrome (DS). Patients with DS can also develop acquired cardiac disorders. Mouse models suggest that a critical 3.7 Mb region located on human chromosome 21 (HSA21) could explain the association with CHDs. This region includes a cluster of genes (IFNAR1, IFNAR2, IFNGR2, IL10RB) encoding for interferon receptors (IFN-Rs). Other genes located on different chromosomes, such as the vascular endothelial growth factor A (VEGFA), have been shown to be involved in cardiac defects. So, we investigated the association between single nucleotide polymorphisms (SNPs) in IFNAR2, IFNGR2, IL10RB and VEGFA genes, and the presence of CHDs or acquired cardiac defects in patients with DS. METHODS: Individuals (n = 102) with DS, and age- and gender-matched controls (n = 96), were genotyped for four SNPs (rs2229207, rs2834213, rs2834167 and rs3025039) using KASPar assays. RESULTS: We found that the IFNGR2 rs2834213 G homozygous genotype and IL10RB rs2834167G-positive genotypes were more common in patients with DSand significantly associated with heart disorders, while VEGFA rs3025039T-positive genotypes (T/*) were less prevalent in patients with CHDs. CONCLUSIONS: We identified some candidate risk SNPs for CHDs and acquired heart defects in DS. Our data suggest that a complex architecture of risk alleles with interplay effects may contribute to the high variability of DS phenotypes.

12q14.3 microdeletion involving HMGA2 gene cause a Silver-Russell syndrome-like phenotype: a case report and review of the literature.

BACKGROUND: Silver-Russell Syndrome (SRS) is a genetic disorder characterized by intrauterine and postnatal growth restriction and normal head circumference with consequent relative macrocephaly. Addictional findings are protruding forehead in early life, body asymmetry (of upper and lower limbs) and substantial feeding difficulties. Although several genetic mechanisms that cause the syndrome are known, more than 40% of patients with a SRS-like phenotype remain without an etiological diagnosis. In the last few years, different clinical reports have suggested that mutations or deletions of the HMGA2 gene can be responsible for a SRS-like phenotype in patients with negative results of the common diagnostic tests for this syndrome. CASE PRESENTATION: We present a 3-year-old male patient with clinical diagnosis of Silver-Russell Syndrome (SRS) associated with a de novo heterozygous deletion of the long arm of the chromosome 12 (12q14.3) encompassing the HMGA2 gene. CONCLUSIONS: Our report confirms the etiological role of HMGA2 as a disease gene in the development of a SRS-like phenotype.

PTEN hamartoma tumor syndromes in childhood: description of two cases and a proposal for follow-up protocol.

PTEN hamartoma tumor syndromes (PHTS) are a spectrum of hamartomatous overgrowth syndromes associated with germ-line mutations in the tumor suppressor PTEN gene located on 10q23.3. It is widely accepted that two of these disorders, Cowden syndrome and Bannayan-Riley-Ruvalcaba syndrome, are allelic conditions. Because PTEN mutations are not identifiable in every case of the PHTS phenotype, the inability to detect a mutation within the PTEN gene does not invalidate the clinical diagnosis of Cowden syndrome, or Bannayan-Riley-Ruvalcaba syndrome, in patients who meet diagnostic criteria for these disorders. PTEN mutations are associated with an increased risk for developing breast, thyroid, endometrial, and sometimes renal cancers. Thus, cancer surveillance is the cornerstone of PHTS patient management. Although a consensus cancer surveillance protocol has not been formally instituted, all PTEN mutation carriers should adopt the cancer surveillance strategies proposed for patients with Cowden syndrome. In addition, because gastrointestinal and vascular complications can be more severe in Bannayan-Riley-Ruvalcaba syndrome than in Cowden syndrome, patients with Bannayan-Riley-Ruvalcaba syndrome should be monitored from this point of view too. In this study, we report on two cases with Bannayan-Riley-Ruvalcaba phenotype that showed two different PTEN mutations. We also propose practice recommendations for management of PHTS patients.

[Metabolic syndrome in children and in adults: is it an autonomous nosological entity?]. / Sindrome metabolica nel bambino e nell'adulto: è ancora un'entità nosologica autonoma?

The term metabolic syndrome defines a cluster of risk factors for cardiovascular diseases and diabetes. This syndrome is very frequent in general population. However, despite the efforts to define the diagnostic criteria, nowadays its clinical utility is object of a lively debate.