Prenatal diagnosis for CF using High Resolution Melting Analysis and simultaneous haplotype analysis through QF-PCR

AbstractBackgroundHigh Resolution Melting (HRM) Analysis is a validated, robust, low-cost, high throughput CF screening method. Here, we report the development and retrospective evaluation of the diagnostic value of a novel multiplex HRM, genotyping and haplotyping method for CF prenatal diagnosis (generic HRM/haplotyping).Methods80 study samples from 20 carrier couples referred for PND (whole blood in EDTA and CVS or amniotic fluid) were genotyped retrospectively using the suggested protocol.ResultsAll DNA samples (variable sources, extraction methods and unknown concentrations) were successfully amplified by the 1st and 2nd round PCR. The Se, Sp, NPV and PPV for the generic HRM/haplotyping method are calculated at 100%.ConclusionsThis generic protocol for PND using HRM, facilitates the simultaneous analysis of DNA samples from various sources in a fast, robust and efficient way. It can be easily adapted and applied for any genetic condition

Systematic documentation and analysis of human genetic variation in hemoglobinopathies using the microattribution approach

We developed a series of interrelated locus-specific databases to store all published and unpublished genetic variation related to hemoglobinopathies and thalassemia and implemented microattribution to encourage submission of unpublished observations of genetic variation to these public repositories. A total of 1,941 unique genetic variants in 37 genes, encoding globins and other erythroid proteins, are currently documented in these databases, with reciprocal attribution of microcitations to data contributors. Our project provides the first example of implementing microattribution to incentivise submission of all known genetic variation in a defined system. It has demonstrably increased the reporting of human variants, leading to a comprehensive online resource for systematically describing human genetic variation in the globin genes and other genes contributing to hemoglobinopathies and thalassemias. The principles established here will serve as a model for other systems and for the analysis of other common and/or complex human genetic diseases

Incontinentia pigmenti revisited. A novel nonsense mutation of the IKBKG gene

Aim: To describe and evaluate the clinical and molecular findings of patients with incontinentia pigmenti (IP) in Greece. Methods: We examined 12 female patients, initially aged 2 weeks to 7 months with clinical diagnosis of IP. Standard tests were performed including skin biopsies and ocular, dental and neurologic examinations. Molecular analysis was carried out on 8 out of 12 cases. Results: The initial clinical examination was stage 1 (vesicular lesions), stage 2 (verrucous lesions) or stage 3 (hyperpigmented linear lesions of the trunk/limbs). At the final clinical examination, 10 of our patients had typical vesicular, verrucous or mixed hyper-hypopigmented skin lesions which had persisted from the neonatal period; seven had delayed dentition or conical teeth; two had developmental delay; one had microcephaly and strabismus and two had scarring alopecia. In seven patients, deletion of exons 4-10 of the IKBKG gene was found. In one patient, skewed X-inactivation was demonstrated and a novel mutation p.Gln332X was found. The mothers’ DNA analyses were all normal. Conclusion: In our sample, all the cases were sporadic and the diagnosis of IP was based mainly on clinical features and confirmed with skin histology. Molecular analysis was used to find the mutations, in some cases to confirm diagnosis and to identify the carriers, which are crucial for prenatal and preimplantation diagnosis

A Clinical Study of Sotos Syndrome Patients With Review of the Literature

Sotos syndrome is characterized by tall stature, advanced bone age, typical facial abnormalities, and developmental delay. The associated gene is NSD1. The study involved 22 patients who fulfilled the clinical criteria. Phenotypic characteristics, central nervous system findings, and cardiovascular and urinary tract abnormalities were evaluated. Meta-analysis on the incidence of cardinal clinical manifestations from the literature was also performed. Macrocephaly was present in all patients. Advanced bone age was noted in 14 of 22 patients (63%), and its incidence presented significant statistical difference in the meta-analysis of previous studies. Some patients had serious clinical manifestations, such as congenital heart defects, dysplastic kidneys, psychosis, and leukemia. Clinical and laboratory examinations should be performed to prevent and manage any unusual medical aspect of the syndrome. Facial gestalt and macrocephaly, rather than advanced bone age, are the strongest indications for clinical diagnosis. (C) 2009 by Elsevier Inc. All rights reserved

Phenotypic and Genotypic Variability in Four Males With MECP2 Gene Sequence Aberrations Including a Novel Deletion

The MECP2 gene mutations cause Rett syndrome (RTT) (OMIM: 312750), an X-linked dominant disorder primarily affecting girls. Until RTT was considered lethal in males, although now approximately 60 cases have been reported. Males with MECP2 mutations present with a broad spectrum of phenotypes ranging from neonatal encephalopathy to nonsyndromic mental retardation (MR). Four boys (aged, 3-11 y) were evaluated for MR. Patient I had autistic features. Patients 2 and 3 were brothers both presenting with psychomotor delay. Patient 4 showed dysmorphic features and behavioral problems reminiscent of FXS. All patients had a normal 46, XY karyotype and three were tested for FXS with negative results. MECP2 gene analysis of exons 3 and 4 was performed using methods based on the PCR, including Enzymatic Cleavage Mismatched Analysis (ECMA) and direct sequencing. Patient I presented somatic mosaicism for the classic RTT p.R106W mutation and patient 4 carried the p.T203M polymorphism. Analysis of the mothers in both cases revealed normal DNA sequences. Patients 2 and 3 had a novel deletion (c.1140del86) inherited from their unaffected mother. MECP2 gene mutations may be considered a rare cause of MR in males although great phenotypic variation hinders genotype-phenotype correlation. (Pediatr Res 67: 551-556, 2010

Gilbert Syndrome as a Predisposing Factor for Cholelithiasis Risk in the Greek Adult Population

We investigated the hypothesis that coinheritance of the common A(TA)(n)TAA promoter mutation at the UGT1A1 locus associated with Gilbert syndrome is a risk factor for gallstone formation in a homogeneous adult population, by conducting a case-control study that included 198 adult patients with cholelithiasis and 152 healthy controls both of Greek origin. Three genotypes were found: 7/7 (17.8% in controls and 23.3% in patients), 6/7 (33.5% in controls and 46.5% in patients), and normal homozygous 6/6 (48.7% in controls and 30.3% in patients). The Gilbert UGT1A1 genotypes 6/7 and 7/7 show significant association (odds ratio 2.225, 95% confidence interval 1.373-3.605, p = 0.001, and odds ratio 2.101, 95% confidence interval 1.171-3.770, p = 0.013, respectively) with cholelithiasis risk. This association supports the theory that genetic factors are responsible for a fraction of symptomatic gallstone disease; however, further studies are required in different ethnic groups to fully elucidate the involvement of Gilbert syndrome in gallstone disease

Genetic Polymorphisms in the UGT1A1 gene and breast cancer risk in Greek women

Uridine diphospho-glucuronosyltransferase 1 (UGT1A1) is involved in estradiol glucuronidation, which may play a central role in the etiology of breast cancer. A common insertion/ deletion polymorphism in the TATAA-box of the promoter region of UGT1A1 results in decreased initiation of transcription, and has been associated with breast cancer risk in different ethnic groups. In the present study, the role of the above genetic variation at the UGT1A1 locus in breast cancer susceptibility was investigated in a homogeneous population. Our case-control study included 136 women with breast cancer and 186 healthy female controls of Greek origin. The polymorphism A(TA) nTAA in the promoter region of UGT1A1 gene was studied using the Fragment Analysis Software of an automated DNA sequencer and three genotypes (homozygous 7/ 7, heterozygous 6/ 7, and normal homozygous 6/ 6) were identified. No significant associations were observed between the 7/ 7 genotype and breast cancer risk, indicating that further studies in Caucasian women are needed to elucidate the role of UGT1A1 polymorphism in breast cancer risk