Clinical,Biological and Genetic Analysis of Prepubertal Isolated Ovarian Cyst in 11 Girls

Background

The cause of isolated gonadotropin-independent precocious puberty (PP) with an ovarian cyst is unknown in the majority of cases. Here, we describe 11 new cases of peripheral PP and, based on phenotypes observed in mouse models, we tested the hypothesis that mutations in the GNAS1, NR5A1, LHCGR, FSHR, NR5A1, StAR, DMRT4 and NOBOX may be associated with this phenotype.

Methodology/Principal Findings

11 girls with gonadotropin-independent PP were included in this study. Three girls were seen for a history of prenatal ovarian cyst, 6 girls for breast development, and 2 girls for vaginal bleeding. With one exception, all girls were seen before 8 years of age. In 8 cases, an ovarian cyst was detected, and in one case, suspected. One other case has polycystic ovaries, and the remaining case was referred for vaginal bleeding. Four patients had a familial history of ovarian anomalies and/or infertility. Mutations in the coding sequences of the candidate genes GNAS1, NR5A1, LHCGR, FSHR, NR5A1, StAR, DMRT4 and NOBOX were not observed.

Conclusions/Significance

Ovarian PP shows markedly different clinical features from central PP. Our data suggest that mutations in the GNAS1, NR5A1, LHCGR, FSHR StAR, DMRT4 and NOBOX genes are not responsible for ovarian PP. Further research, including the identification of familial cases, is needed to understand the etiology of ovarian PP.     

Missense mutation G296S in GATA4 is not responsible for cardiac septal defects

BACKGROUND:

The most common type of congenital heart disease is the cardiac septal defects, which has reported to be caused by a missense mutation (G296S) in exon 3 of the GATA4 gene.

AIMS:

The present study was undertaken to find out whether GATA4 gene is the prime cause of the septal defects in Mysore population.

MATERIALS AND METHODS:

GATA4 gene analyses were undertaken on 21 confirmed CHD cases by PCR and DNA sequencing.

RESULTS AND CONCLUSION:

Analysis of this particular mutation in 21 septal defect patients revealed that none of the patients had the mutation, indicating that this mutation is population specific or septal defect in Mysore population is caused due to mutations in other regions of the GATA4 gene.     

Identification of FVIII gene mutations in patients with hemophilia A using new combinatorial sequencing by hybridization

BACKGROUND:

Standard methods of mutation detection are time consuming in Hemophilia A (HA) rendering their application unavailable in some analysis such as prenatal diagnosis.

OBJECTIVES:

To evaluate the feasibility of combinatorial sequencing-by-hybridization (cSBH) as an alternative and reliable tool for mutation detection in FVIII gene.

PATIENTS/METHODS:

We have applied a new method of cSBH that uses two different colors for detection of multiple point mutations in the FVIII gene. The 26 exons encompassing the HA gene were analyzed in 7 newly diagnosed Italian patients and in 19 previously characterized individuals with FVIII deficiency.

RESULTS:

Data show that, when solution-phase TAMRA and QUASAR labeled 5-mer oligonucleotide sets mixed with unlabeled target PCR templates are co-hybridized in the presence of DNA ligase to universal 6-mer oligonucleotide probe-based arrays, a number of mutations can be successfully detected. The technique was reliable also in identifying a mutant FVIII allele in an obligate heterozygote. A novel missense mutation (Leu1843Thr) in exon 16 and three novel neutral polymorphisms are presented with an updated protocol for 2-color cSBH.

CONCLUSIONS:

cSBH is a reliable tool for mutation detection in FVIII gene and may represent a complementary method for the genetic screening of HA patients.     

Genetic and molecular analysis of the CLDN14 gene in Moroccan family with non-syndromic hearing loss

BACKGROUND:

Hearing loss is the most prevalent human genetic sensorineural defect. Mutations in the CLDN14 gene, encoding the tight junction claudin 14 protein expressed in the inner ear, have been shown to cause non-syndromic recessive hearing loss DFNB29.

AIM:

We describe a Moroccan SF7 family with non-syndromic hearing loss. We performed linkage analysis in this family and sequencing to identify the mutation causing deafness.

MATERIALS AND METHODS:

Genetic linkage analysis, suggested the involvement of CLDN14 and KCNE1 gene in deafness in this family. Mutation screening was performed using direct sequencing of the CLDN14 and KCNE1 coding exon gene.

RESULTS:

Our results show the presence of c.11C>T mutation in the CLDN14 gene. Transmission analysis of this mutation in the family showed that the three affected individuals are homozygous, whereas parents and three healthy individuals are heterozygous. This mutation induces a substitution of threonine to methionine at position 4.

CONCLUSION:

These data show that CLDN14 gene can be i mplicated in the development of hearing loss in SF7 family; however, the pathogenicity of c.11C>T mutation remains to be determined.     

A homozygous female hemophilia A

BACKGROUND:

Hemophilia A (HA), being an X-linked recessive disorder, females are rarely affected, although they can be carriers.

AIMS:

To study the mutation in F8 gene in an extended family with a homozygous female HA.

MATERIALS AND METHODS:

All the seven affected members (six males and one female) were initially screened by Conformation Sensitive Gel Electrophoresis (CSGE) and direct DNA sequencing.

RESULTS:

A homozygous missense mutation c.1315G>A (p.Gly420Ser) was identified in exon 9 of F8 gene in homozygous state in the affected female born of 1° consanguinous marriage and in all the affected male members of the family. Her factor VIII levels was found to be 5.5%, vWF:Ag 120%.

CONCLUSION:

In India, as consanguineous marriages are very common in certain communities (up to 30%), the likelihood of encountering female hemophilia is higher, although this is the first case of HA out of 1600 hemophilia families registered in our Comprehensive Haemophilia Care Center. Genetic diagnosis in such cases is not necessary as all the male children will be affected and daughters obligatory carriers.     

Nucleotide sequence analysis of NIPBL gene in Indian Cornelia de Lange syndrome cases

BACKGROUND:

Cornelia de Lange syndrome (CdLS) is a multisystem developmental disorder in children. The disorder is caused mainly due to mutations in Nipped-B-like protein. The molecular data for CdLS is available from developed countries, but not available in developing countries like India. In the present study, the hotspot region of NIPBL gene was screened by Polymerase Chain Reaction which includes exon 2, 22, 42, and a biggest exon 10, in six CdLS patients and ten controls.

MATERIALS AND METHODS:

The method adopted in present study was amplification of the target exon by using polymerase chain reaction, qualitative confirmation of amplicons by Agarose Gel Electrophoresis and use of amplicons for Conformation Sensitive Gel Electrophoresis to find heteroduplex formation followed by sequencing.

RESULTS:

We report two polymorphisms in the studied region of gene NIPBL. The polymorphisms are in the region of intron 1 and in exon 10. The polymorphism C/A is present in intron 1 region and polymorphism T/G in exon 10.

CONCLUSION:

The intronic region polymorphism may have a role in intron splicing whereas the polymorphism in exon 10 results in amino acid change (Val to Gly). These polymorphisms are disease associated as these are found in CdLS patients only and not in controls.     

The NQO1 allelic frequency in hindu population of central India varies from that of other Asian populations

CONTEXT:

The enzymes encoded by the polymorphic genes NAD (P) H: quinone oxidoreductase 1 (NQO1) play an important role in the activation and inactivation of xenobiotics. This enzyme has been associated with xenobiotic related diseases, such as cancer, therapeutic failure and abnormal effects of drugs.

AIM:

The aim of the present study was to determine the allelic and genotypic frequencies of NQO Hinf I polymorphisms in a Hindu population of Central India.

SETTINGS AND DESIGN:

Polymorphisms of NQO1 were determined in 311 unrelated Hindu individuals.

MATERIALS AND METHODS:

Polymerase chain reaction- Restriction Fragment Length Polymorphism (PCR-RFLP) analysis in peripheral blood DNA for NQO1 Hinf I polymorphism was used in 311 unrelated Hindu individuals.

STATISTICAL ANALYSIS:

Allele frequencies were calculated by direct counting. Hardy Weinberg Equilibrium was evaluated using a Chi-square goodness of fit test.

RESULTS:

The observed allelic frequency was 81% for C (wild) and 19% for T (mutant) in the total sample.

CONCLUSIONS:

The allelic frequency of “C” was higher than in other Asians (57%), but similar to Caucasians (81%). The genotype distributions for Hinf I polymorphisms were in Hardy-Weinberg equilibrium.