NF1 gene mutations represent the major molecular event underlying neurofibromatosis-Noonan syndrome.

Neurofibromatosis type 1 (NF1) demonstrates phenotypic overlap with Noonan syndrome (NS) in some patients, which results in the so-called neurofibromatosis-Noonan syndrome (NFNS). From a genetic point of view, NFNS is a poorly understood condition, and controversy remains as to whether it represents a variable manifestation of either NF1 or NS or is a distinct clinical entity. To answer this question, we screened a cohort with clinically well-characterized NFNS for mutations in the entire coding sequence of the NF1 and PTPN11 genes.

Familial recurrence of nonsyndromic congenital heart defects in first degree relatives of patients with deletion 22q11.2.

The majority of nonsyndromic congenital heart defects (CHDs) are considered to follow a multifactorial model of inheritance. Multiple family members affected by CHD can occasionally be detected, and the involvement of several genetic loci interacting with environmental factors is suspected to be implicated. The DiGeorge/velo-cardio-facial syndrome related to microdeletion 22q11.

ZFPM2/FOG2 and HEY2 genes analysis in nonsyndromic tricuspid atresia.

Tricuspid atresia (TriAt), the third most common cyanotic congenital heart defect (CHD), consists of complete lack of tricuspid valve formation, with no connection between the right atrium and the right ventricle. To date, the genetic mechanism responsible of TriAt is still obscure. However, animal models have suggested a role of cardiogenic Zfpm2/Fog2 and Hey2 genes in the pathogenesis of TriAt.

Mutations of the Nogo-66 receptor (RTN4R) gene in schizophrenia.

Schizophrenia (SCZD) or schizoaffective disorders are quite common features in patients with DiGeorge/velo-cardio-facial syndrome (DGS/VCFS) as a result of chromosome 22q11.2 aploinsufficiency. We evaluated the Nogo-66 receptor gene (RTN4R), which maps within the DGS/VCFS critical region, as a potential candidate for schizophrenia susceptibility.

A novel PTPN11 gene mutation bridges Noonan syndrome, multiple lentigines/LEOPARD syndrome and Noonan-like/multiple giant cell lesion syndrome.

Noonan (NS) and multiple lentigines/LEOPARD syndromes (LS) have proved to be associated with distinct PTPN11 mutations. Noonan-like/multiple giant cell lesion syndrome (NLS) is a rare disease, characterised by short stature, facial dysmorphisms, congenital heart defect (CHD) and central giant cell lesions. PTPN11 gene mutations have been reported in a single NLS family and two sporadic patients.

LEOPARD syndrome: a new polyaneurysm association and an update on the molecular genetics of the disease.

LEOPARD syndrome, one of many cardiocutaneous syndromes, is an acronym for some of the obvious manifestations of the disease, such as lentigines or ocular hypertelorism. The synonymous name progressive cardiomyopathic lentiginosis better indicates the morbid cardiac features that patients with the syndrome have. A patient with LEOPARD syndrome is presented.

Familial aggregation of genetically heterogeneous hypertrophic cardiomyopathy: a boy with LEOPARD syndrome due to PTPN11 mutation and his nonsyndromic father lacking PTPN11 mutations.

Background: Nonsyndromic hypertrophic cardiomyopathy (HCM) is a primary cardiac disease transmitted as an autosomal dominant trait. Multiple chromosomal loci have been found to be involved in the etiology of this defect. LEOPARD syndrome is a genetic condition characteristically associated with HCM.

Mutations of ZFPM2/FOG2 gene in sporadic cases of tetralogy of Fallot.

Two out of 47 patients with sporadic tetralogy of Fallot (TOF), the most common cyanotic conotruncal heart defect (CTD), showed heterozygous missense mutations of the ZFPM2/FOG2 gene. Knockout mice carrying mutations in the ZFPM2/FOG2 gene have similarly been found to exhibit TOF. While both mutant ZFPM2/FOG2 proteins, E30G (c.

Analysis of intracellular distribution and apoptosis involvement of the Ufd1l gene product by over-expression studies.

UFD1L is the human homologue of the yeast ubiquitin fusion degradation 1 (Ufd1) gene and maps on chromosome 22q11.2 in the typically deleted region (TDR) for DiGeorge/velocardiofacial syndromes (DGS/VCFS). In yeast, Ufd1 protein is involved in a degradation pathway for ubiquitin fused products (UFD pathway).

DiGeorge subtypes of nonsyndromic conotruncal defects: evidence against a major role of TBX1 gene.

The role of the 22q11 region genes, and among them TBX1, in nonsyndromic conotruncal defects (CTDs) is still unclear. Mice hemizygous at the Tbx1 locus show a remarkable incidence of heart outflow tract anomalies, of the same type commonly found in DiGeorge/Velo-cardio-facial syndrome (DGS/VCFS). Mutation analysis of the TBX1 gene in isolated, nonsyndromic CTDs has not demonstrated any functional pathogenetic variation so far.

Association study between CAG trinucleotide repeats in the PCQAP gene (PC2 glutamine/Q-rich-associated protein) and schizophrenia.

Schizophrenia or schizoaffective disorders are quite common features in patients with DiGeorge/velocardiofacial syndrome (DGS/VCFS) as a result of hemizygosity of chromosome 22q11.2. We evaluated the PCQAP gene, which maps within the DGS/VCFS interval, as a potential candidate for schizophrenia susceptibility.

Grouping of multiple-lentigines/LEOPARD and Noonan syndromes on the PTPN11 gene.

Multiple-lentigines (ML)/LEOPARD (multiple lentigines, electrocardiographic-conduction abnormalities, ocular hypertelorism, pulmonary stenosis, abnormal genitalia, retardation of growth, and sensorineural deafness) syndrome is an autosomal dominant condition--characterized by lentigines and café au lait spots, facial anomalies, cardiac defects--that shares several clinical features with Noonan syndrome (NS). We screened nine patients with ML/LEOPARD syndrome (including a mother-daughter pair) and two children with NS who had multiple café au lait spots, for mutations in the NS gene, PTPN11, and found, in 10 of 11 patients, one of two new missense mutations, in exon 7 or exon 12. Both mutations affect the PTPN11 phosphotyrosine phosphatase domain, which is involved in <30% of the NS PTPN11 mutations.

Functional characterization of the 5' flanking region of human ubiquitin fusion degradation 1 like gene (UFD1L).

UFD1L (Ubiquitin Fusion Degradation 1 Like) gene encodes for a component of a multi-complex involved in the degradation of ubiquitin fusion proteins. The gene maps on chromosome 22q11, in a region commonly deleted in severe congenital disorders such as DiGeorge (DGS) and velo-cardio-facial (VCFS) syndromes. UFD1L is a single copy gene ubiquitously expressed in high levels in the pharyngeal pouches and fourth branchial arch artery during development.