Clinical expression and mitochondrial deoxyribonucleic acid study in twins with 14484 Leber's hereditary optic neuropathy: A case report.

Background: This study aimed to explore clinical and molecular factors that cause discordance for clinical expression of Leber's hereditary optic neuropathy (LHON) in a pair of identical twins with the 14484 point mutation.

Case Summary: Twin patients with the 14484 point mutation were studied for zygosity by using the Short Tandem Repeats Typing system. For the monozygotic twins, the radioactive restriction and densitometric analyses were used to quantitate the heteroplasmy level for the 14484 point mutation.

Association of Mitochondrial DNA Polymorphisms With Pediatric-Onset Cyclic Vomiting Syndrome.

Background: Cyclic vomiting syndrome (CVS) is a functional gastrointestinal disorder characterized by recurrent stereotypic episodes of vomiting. The pathophysiology of CVS remains obscure. Previous studies have supported the hypotheses of mitochondrial dysfunction.

The prehistoric peopling of Southeast Asia.

The human occupation history of Southeast Asia (SEA) remains heavily debated. Current evidence suggests that SEA was occupied by Hòabìnhian hunter-gatherers until ~4000 years ago, when farming economies developed and expanded, restricting foraging groups to remote habitats. Some argue that agricultural development was indigenous; others favor the "two-layer" hypothesis that posits a southward expansion of farmers giving rise to present-day Southeast Asian genetic diversity.

Whole Exome Sequencing in Eight Thai Patients With Leber Congenital Amaurosis Reveals Mutations in the CTNNA1 and CYP4V2 Genes.

Purpose: Our goal was to describe the clinical and molecular genetic findings in Thai patients with Leber congenital amaurosis (LCA).

Methods: Whole exome sequencing (WES) was performed in eight unrelated patients. All genes responsible for inherited retinal diseases (IRDs) based on RetNet were selected for analysis.

Exome sequencing in Thai patients with familial obesity.

Obesity is a major worldwide health issue, with increasing prevalence in adults and children from developed and developing countries. Obesity causes several chronic diseases, including cardiovascular and respiratory diseases, osteoarthritis, hypertension, stroke, type II diabetes, obstructive sleep apnea, and several types of cancer. Previous genome-wide association studies have identified several genes associated with obesity, including LEP, LEPR, POMC, PCSK1, FTO, MC3R, MC4R, GNPDA2, TMEM18, QPCTL/GIPR, BDNF, ETV5, MAP2K5/SKOR1, SEC16B, SIM1, and TNKS/MSRA.

A novel start codon mutation of the MERTK gene in a patient with retinitis pigmentosa.

Purpose: Retinitis pigmentosa (RP) is a clinically and genetically heterogeneous group of inherited retinal degenerations characterized by progressive loss of photoreceptor cells and RPE functions. More than 70 causative genes are known to be responsible for RP. This study aimed to identify the causative gene in a patient from a consanguineous family with childhood-onset severe retinal dystrophy.

Profiling the mitochondrial proteome of Leber's Hereditary Optic Neuropathy (LHON) in Thailand: down-regulation of bioenergetics and mitochondrial protein quality control pathways in fibroblasts with the 11778G>A mutation.

Leber's Hereditary Optic Neuropathy (LHON) is one of the commonest mitochondrial diseases. It causes total blindness, and predominantly affects young males. For the disease to develop, it is necessary for an individual to carry one of the primary mtDNA mutations 11778G>A, 14484T>C or 3460G>A.

Development of a SNP set for human identification: A set with high powers of discrimination which yields high genetic information from naturally degraded DNA samples in the Thai population.

This study describes the development of a SNP typing system for human identification in the Thai population, in particular for extremely degraded DNA samples. A highly informative SNP marker set for forensic identification was identified, and a multiplex PCR-based Invader assay was developed. Fifty-one highly informative autosomal SNP markers and three sex determination SNP markers were amplified in two multiplex PCR reactions and then detected using Invader assay reactions.

Whole exome sequencing in Thai patients with retinitis pigmentosa reveals novel mutations in six genes.

Purpose: To identify disease-causing mutations and describe genotype-phenotype correlations in Thai patients with nonsyndromic retinitis pigmentosa (RP).

Methods: Whole exome sequencing was performed in 20 unrelated patients. Eighty-six genes associated with RP, Leber congenital amaurosis, and cone-rod dystrophy were analyzed for variant detection.

Mitochondrial DNA history of Sri Lankan ethnic people: their relations within the island and with the Indian subcontinental populations.

Located only a short distance off the southernmost shore of the Greater Indian subcontinent, the island of Sri Lanka has long been inhabited by various ethnic populations. Mainly comprising the Vedda, Sinhalese (Up- and Low-country) and Tamil (Sri Lankan and Indian); their history of settlements on the island and the biological relationships among them have remained obscure. It has been hypothesized that the Vedda was probably the earliest inhabitants of the area, followed by Sinhalese and Tamil from the Indian mainland.

Identification of the variants in PARL, the nuclear modifier gene, responsible for the expression of LHON patients in Thailand.

The present study explored variation in the PARL gene as one of the potential nuclear modifiers in the pathogenesis of Leber hereditary optic neuropathy (LHON). Ten exons, their franking introns and 3' UTR of the PARL gene were analysed. Seventeen SNPs detected were investigated in 83 affected and 53 unaffected individuals from 47 independent Thai LHON pedigrees using MQLS statistics in order to minimize the influence of the family background.

Polyglutamined expanded androgen receptor interacts with chaperonin CCT.

CCT chaperonin is a highly conserved molecular chaperone, which plays an important role in the folding of complex proteins in mammalian cells. CCT chaperonin interacts with huntingtin and results in decrease of aggregate formation followed by increase of cell survival. Using yeast-two-hybrid system, we screen for specific CCT chaperonin subunit, which can recognize and bind to androgen receptor.

Stability of epitheliotrophic factors in autologous serum eye drops from chronic Stevens-Johnson syndrome dry eye compared to non-autoimmune dry eye.

Purpose: To compare the concentrations of epitheliotrophic factors in autologous serum eye drops (ASE) prepared from sera of chronic Stevens-Johnson syndrome (SJS) patients with dry eyes to those prepared from non-autoimmune dry eye controls and to study the stability of the epitheliotrophic factors in different storage conditions.

Methods: Twenty-percent ASE were prepared from 10 chronic SJS patients with dry eyes and 10 age-matched non-autoimmune dry eye controls. The concentrations of major epitheliotrophic factors comprising epidermal growth factor (EGF), transforming growth factor-beta1 (TGF-β1), transforming growth factor-beta2 (TGF-β2), and fibronectin in those ASE preparations were determined by enzyme-linked immunosorbent assay (ELISA) at baseline and after different storage conditions: at 4 °C for 1 week and 1 month; and at -20 °C for 1, 3 and 6 months.

Mitochondrial haplogroup background may influence Southeast Asian G11778A Leber hereditary optic neuropathy.

Purpose: To investigate the role of mitochondrial DNA (mt DNA) background on the expression of Leber hereditary optic neuropathy (LHON) in Southeast Asian carriers of the G11778A mutation.

Methods: Complete mtDNA sequences were analyzed from 53 unrelated Southeast Asian G11778A LHON pedigrees in Thailand and 105 normal Thai controls, and mtDNA haplogroups were determined. Clinical phenotypes were tested for association with mtDNA haplogroup, with adjustment for potential confounders such as sex and age at onset.

Genome-wide linkage scan and association study of PARL to the expression of LHON families in Thailand.

Leber hereditary optic neuropathy (LHON) is the most common mitochondrially inherited disease causing blindness, preferentially in young adult males. Most of the patients carry the G11778A mitochondrial DNA (mtDNA) mutation. However, the marked incomplete penetrance and the gender bias indicate some additional genetic and/or environmental factors to disease expression.

Characterization of 2-deoxy-D-glucose uptake in fibroblast cultures derived from patients with A3243G mitochondrial DNA mutation.

We investigated cellular glucose uptake of fibroblast cultures derived from seven patients with mitochondrial DNA (mtDNA) A3243G mutation and from six healthy controls with no mtDNA mutations. Heteroplasmy of fibroblast cultures were shifted by culturing for 5 days in galactose-containing medium. The proportion of mutant mtDNA decreased by 7.

Genetic history of Southeast Asian populations as revealed by ancient and modern human mitochondrial DNA analysis.

The 360 base-pair fragment in HVS-1 of the mitochondrial genome were determined from ancient human remains excavated at Noen U-loke and Ban Lum-Khao, two Bronze and Iron Age archaeological sites in Northeastern Thailand, radio-carbon dated to circa 3,500-1,500 years BP and 3,200-2,400 years BP, respectively. These two neighboring populations were parts of early agricultural communities prevailing in northeastern Thailand from the fourth millennium BP onwards. The nucleotide sequences of these ancient samples were compared with the sequences of modern samples from various ethnic populations of East and Southeast Asia, encompassing four major linguistic affiliations (Altaic, Sino-Tibetan, Tai-Kadai, and Austroasiatic), to investigate the genetic relationships and history among them.

Mitochondrial DNA haplogroup distribution in pedigrees of Southeast Asian G11778A Leber hereditary optic neuropathy.

To investigate the association of mitochondrial DNA (mtDNA) haplogroups and Leber hereditary optic neuropathy (LHON) in the Southeast Asian population, mtDNA haplogroup determination was performed by high-resolution restriction fragment length polymorphism in 42 patients with LHON who were carrying the G11778A mutation and in control subjects drawn from a Thai urban population unaffected by LHON. The patients with LHON were of Thai, Thai-Chinese, and Indian origin. Three mtDNA haplogroups, M, B*, and B, were found in LHON patients in a frequency similar to that in control subjects.

Transmission of heteroplasmic G11778A in extensive pedigrees of Thai Leber hereditary optic neuropathy.

Leber hereditary optic neuropathy (LHON) is characterized by the acute or subacute bilateral painless loss of central vision, predominantly in young males. G11778A is the most common mitochondrial DNA mutation responsible for the disease. Thirty-seven percent of our LHON pedigrees (which is a much higher prevalence than that generally found) carried heteroplasmic G11778A.

The unique characteristics of Thai Leber hereditary optic neuropathy: analysis of 30 G11778A pedigrees.

Leber hereditary optic neuropathy (LHON) is characterized by acute or subacute bilateral visual loss, and affects mostly young males. The most common mitochondrial DNA mutation responsible for LHON worldwide is G11778A. Despite different genetic backgrounds, which are believed to influence the disease expression, most features of LHON are quite common in different populations.

Proportion of 11778 mutant mitochondrial DNA and clinical expression in a thai population with leber hereditary optic neuropathy.

Background: The proportion of mutant mtDNA in blood has been found to correlate with the frequency of visual loss in cases with mtDNA mutations associated with Leber hereditary optic neuropathy (LHON), especially in men. We sought to determine this correlation in a Thai population of LHON.

Methods: Densitometric quantification of blood mtDNA with the 11,778 LHON mutation in 137 symptomatic cases and their asymptomatic maternal relatives in 30 Asian pedigree families was performed.

Oculopharyngodistal myopathy in a Thai family.

There has been controversy whether oculopharyngodistal myopathy (OPDM) commonly seen in Japan is a distinct disease entity or a variant of oculopharyngeal muscular dystrophy (OPMD) initially described in French-Canadians and has since been reported in other ethnic groups. Both diseases have autosomal dominant inheritance and OPDM patients are clinically similar to OPMD with slowly progressive ptosis, ophthalmoplegia and dysphagia except that most of the former usually have distal as opposed to proximal weakness and most of them are genetically different from the latter The authors report here 2 siblings with clinical features of OPDM. This entity is rare outside Japan and this is the first family to be reported from Thailand

An unusual family with Leber's hereditary optic neuropathy and facioscapulohumeral muscular dystrophy.

We performed an observational prospective analysis to study the clinical characteristics as well as a molecular genetic analysis of 17 members of a Thai family who had visual loss and/or muscle weakness. Their blood mitochondrial DNA were examined for the presence of the G11778A Leber's hereditary optic neuropathy (LHON) mutation. Facioscapulohumeral muscular dystrophy (FSHD) DNA analysis was performed in four members who had visual loss.

Case report: A Thai patient with Leber's hereditary optic neuropathy linked to mitochondrial DNA 14484 mutation.

A young Thai male presented with bilateral visual loss and disc pallor. The 14484 mutation responsible for Leber's hereditary optic neuropathy (LHON) was identified on blood mitochondrial analysis. His visual loss was more severe than the visual loss described in Caucasian and Japanese patients and showed no improvement.

An A-71C substitution in a green gene at the second position in the red/green visual-pigment gene array is associated with deutan color-vision deficiency.

We studied 247 Japanese males with congenital deutan color-vision deficiency and found that 37 subjects (15.0%) had a normal genotype of a single red gene followed by a green gene(s). Two of them had missense mutations in the green gene(s), but the other 35 subjects had no mutations in either the exons or their flanking introns.