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PAGOD Syndrome is an acronym for lung and pulmonary arteries hypoplasia, agonadism, omphalocele / diaphragmatic defect and dextrocardia. A series of 21 patients is described, where 90.5% had a 46,XY karyotype and only two cases 46,XX; 66.6% exhibited a female phenotype and 28.6% ambiguous genitalia. The occurrence of two patients 46,XX excludes the Y chromosome as a carrier of the genetic defect and raises the possibility of a recessive X-linked inheritance, without ruling out that the observed cases in siblings may be due to mutations in other genes as Stra6, VEGFA, VEGFB, VEGFC, and alternative splicing of transcripts VEGFA, HIF1, HIF2, among others. Congenital malformations were observed in patients’ genitals and gonads 85.7%, 66.6% in diaphragm and abdominal wall , heart 80.9%, 71.4% lungs, blood vessels 80.9% and 42.8% in abdomen. The review of patients has demonstrated a high degree of variability in the expression of malformations of organs and organ systems. Vascular malformations represent an important and characteristic component of PAGOD syndrome and whose base morphogenetic syndrome may be due to a defect in early embryonic angiogenesis with impact on organogenesis and system development. Among genes related to vascular remodeling during embryogenesis, tissue regeneration and carcinogenesis, the Endothelial Growth Factor D Vascular (VEGFD), located in the Xp22.31 region, with expression in lung, heart, small intestine, uterus, breast, neuroblastoma and neural tissue, represents a strong candidate for molecular analysis as a cause of the syndrome.

Hereditary forms of multiple exostoses, now called EXT1/EXT2-CDG within Congenital Disorders of Glycosylation, are the most common benign bone tumors in humans and clinical description consists of the formation of several cartilage-capped bone tumors, usually benign and localized in the juxta-epiphyseal region of long bones, although wide body dissemination in severe cases is not uncommon. Onset of the disease is variable ranging from 2-3 years up to 13-15 years with an estimated incidence ranging from 1/18,000 to 1/50,000 cases in European countries. We present a double mutant alleles in the EXT1 gene not previously reported in a teenager and her family with hereditary multiple exostoses.

Autism is a complex neurodevelopmental disorder characterized by impairment of social interaction, language, communication, and stereotyped, repetitive behavior. Genetic predisposition to autism has been demonstrated from families and twin studies. Despite recent advances in identifying some susceptibility candidate genes, its underlying neurological mechanism is uncertain. There are genetic, biochemical and neuropathological findings that support the hypothesis that autism could be caused by GABAergic dysfunction and it is partially responsible for the etiology of this disorder. One of the most studied genome regions is the 15q11-q13, where the genes that encode for beta3, alpha5 and gamma3 subunits of the GABAA receptor are located. This review demonstrates evidence that involves this region in autism susceptibility and its likely relation with the hypothesis of GABAergic dysfunction.

Autism is a complex neurodevelopmental disorder characterized by impairment of social interaction, language, communication, and stereotyped, repetitive behavior. Genetic predisposition to Autism has been demonstrated in families and twin studies. There is evidence (linkage and genetic association, biochemical, neuropathological, functional and cytogenetic) that the gamma-amino-butyric acid receptor beta 3 subunit gene (GABRB3) at 15q11-q13 is a susceptibility candidate gene for Autism. The aim of this exploratory study was to identify new variants of this gene. We performed the molecular analysis (SSCP/Sequencing) of 10 exons and its intronic flanking regions of GABRB3, using a candidate gene screening approach in 18 idiopathic autistic patients. We did not find non-synonymous mutations at the encoding regions, but we identified four SNP (Single Nucleotide Polymorphism). The first one, represented a silent mutation p.P25P in exon la and was found in 33.33% of the patients. The second one: IVS3 + 13C > T (5b far from the intron 5' consensus sequence), was found in 44.44% of the patients, while it was also identified in 16.67% of the controls. Simultaneously, 33.33% of the patients had both variants, and although, 16.67% of the controls also had the same combination of variants, 66.66% of the patients with those alleles had a familiar history of Autism. The third and fourth SNP: IVS5 + 40T > G and IVS-70A > G were identified in two different patients. None of the last three SNPs have been reported at the SNP database (dbSNP). The proximity of SNP: IVS3 + 13C > T with the consensus and interaction sequence with U1 nucleoriboprotein, could disturb the normal splicing of mRNA. This is in agreement with the evidence of lower levels of GABA-A receptors in autistic brains; so, it could be a common variant, that by itself could not cause a phenotypic effect, but joined to other variants with the same gene, in different related genes or with epigenetic changes, could explain the autistic phenotype and its heterogeneity.

Zulia is a state located in the northwest of Venezuela. Congenital malformations, deformities and chromosomal anomalies are the second cause of infant and neonatal mortality. There are seven public and private groups providing genetic services, the most important of which, the Medical Genetic Unit at the Zulia University was created in 1973. So far, this unit has provided genetic services to 12,000 families, and has been responsible for undergraduate and postgraduate education in human and medical genetics. Prenatal diagnosis is performed at the Unit and a private practice group, the most frequent referral reason being advanced maternal age. The most frequent genetic diseases in the state are Huntington's disease, sickle cell anemia, neural tube defects and Down's syndrome. Research in genetics includes the clinical, epidemiological and molecular characterization of hereditary diseases, cancer, reproductive problems and genetic diversity. Other public groups are conducting research on dementias, including Alzheimer's disease, and on the genotoxic effects of environmental pollutants., (Copyright (c) 2004 S. Karger AG, Basel.)

A 9-year-old patient with the classical clinical picture of Hutchinson-Gilford progeria (HGP) is described. The karyotype shows a 46,XY,del(1)(q23) constitution. Our findings suggest that the interval 1q23 may play a roll in the etiology of HGP. A perturbation in glycosylation in connective tissue has been demonstrated in patients with this condition. This abnormality may be due to a defect in the UDP-galactose:beta-N-acetylglucosamina-beta-1,4-galactosyltransferase 3 (B4GALT3) gene that has been mapped in the interval 1q21-23. The cytogenetical analyses of this patient suggest that the B4GALT3 gene could be involved in the pathogenesis of HGP., (Copyright 2002 Wiley-Liss, Inc.)

Werner in 1915, described a patient is characterized by a tibial bilateral aplasia or hypoplasia, polydactyly and absent thumbs. Autosomal dominant inheritance is demonstrated, with variable expressivity. The objective of this work is to describe a child with clinic and radiologic signs of Tibial Hypoplasia with Polydactyly. The genealogic study allowed us to suppose that the gene has a variable expressivity, since in the maternal branch, malformations such as syndactyly of hands, proximal implantation of thumbs and tibiae vara, have been found. The clinic, radiologic, and genetic aspects are discussed.

Cystic Fibrosis (CF) is a severe and relatively common autosomic recessive disease caused by a variety of mutations in the CFTR gene. The most frequent mutation worldwide, consists of the deletion of the phenylalanine codon at position 508 (delta F508). Here we report the first cases of prenatal diagnosis of CF by DNA analysis in couples at risk in Venezuela. The study focused on the detection of delta F508 alleles analyzing DNA recovered directly from amniocytes or from their cultures, using the polymerase chain reaction (PCR) and polyacrylamide gel electrophoresis. Two of three fetuses resulted homozygotic for the delta F508 allele and the third one turned out to be a delta F508 carrier. This information sustained the genetic counseling of the couples and allowed them to take objective reproductive decisions, a direct consequence of the availability of gene analysis at the DNA level.

In 1964, Pfeiffer described a syndrome consisting of craniosynostosis, broad thumbs, broad great toes, and partial soft tissue syndactyly of the hands and feet. It belongs to acrocephalosyndactyly syndromes. We describe a male baby product of an eighth full-term uncomplicated uncontrolled pregnancy, mother and father normal and unrelated, 32 and 50 years old, respectively. He had all diagnostic and prognostic criteria of Subtype 2 Pfeiffer's Syndrome. The clinical, radiological, tomographic, and genetic aspects are discussed.

Duchenne and Becker muscular dystrophy (DMD/BMD) are recessive X-linked neuromuscular diseases produced by allelic mutations in the human dystrophin gen. In the present study we determined the 14-deletion prone exons by multiplex PCR in 24 no related venezuelan patients with clinical diagnosis of DMD/BMD. We found 37% of intragenic deletions of which 77% were located at the "hot spot" deletion region that includes exons 44 to 55. The present study show that deletion frequency observed in venezuelan patients resembles some Asian populations and is lower than that observed in Europe and North America. The explanation of the low frequency detected in our patients is beyond the present study, but it is likely that different mutations, ocurring at other regions of the gene is determining a molecular heterogeneity of the DMD/BMD disease in Venezuela.