Evaluation of FTO rs9939609 and MC4R rs17782313 polymorphisms as prognostic biomarkers of obesity: a population-based cross-sectional study

Objectives: Obesity is a significant risk factor for a number of chronic diseases, including diabetes, cardiovascular diseases, and cancer. Obesity usually results from a combination of causes and contributing factors, including genetics and lifestyle choices. Many studies have shown an association of single nucleotide polymorphisms [SNPs] in the fat mass and obesity-associated [FTO] and the melanocortin-4 receptor [MC4R] genes with body mass index [BMI]. Therefore, recognizing the main genes and their relevant genetic variants will aid prediction of obesity risk. The aim of our study was to investigate the frequency of rs9939609 and rs17782313 polymorphisms in FTO and MC4R genes in an Iranian population

Methods: We enrolled 130 obese patients and 83 healthy weight controls and calculated their BMI. Genomic DNA was extracted from peripheral blood and the frequency of rs9939609 and rs17782313 polymorphisms in FTO and MC4R genes was determined using the tetra-primer amplification refractory mutation system-polymerase chain reaction [ARMS-PCR]

Results: Significant associations were found between FTO rs9939609 and BMI. Where homozygous risk allele carriers [A-A] have significant higher odds ratio [OR] of being obese than individuals with normal BMI [OR = 6.927, p < 0.005, 95% confidence interval [CI]: 3.48–13.78]. No significant correlation between MC4R rs17782313 and obesity were observed when compared to healthy weight individuals. Although subjects with C-C genotype had higher odds of obesity [OR = 1.889, p = 0.077, 95% CI: 0.92–3.84]

Conclusions: This study shows a relationship between FTO polymorphism and increased BMI, therefore, SNP in the FTO gene influence changes in BMI and can be considered a prognostic marker of obesity risk

Mitochondrial variants in pompe disease: a comparison between classic and non-classic forms

Objective: Pompe disease [PD] is a progressive neuromuscular disorder that is caused by glucosidase acid alpha [GAA] deleterious mutations. Mitochondrial involvement is an important contributor to neuromuscular diseases. In this study the sequence of MT-ATP 6/8 and Cytochrome C oxidase I/II genes along with the expression levels of the former genes were compared in classic and non-classic patients

Materials and Methods: In this case-control study, the sequence of MT-ATP 6/8 and Cytochrome C oxidase was analyzed by polymerase chain reaction [PCR]-Sanger sequencing and expression of MT-ATP genes were quantified by real time-PCR [RT-PCR] in 28 Pompe patients. The results were then compared with 100 controls. All sequences were compared with the revised Cambridge reference sequence as reference

Results: Screening of MT-ATP6/8 resulted in the identification of three novel variants, namely T9117A, A8456C and A8524C. There was a significant decrease in MT-ATP6 expression between classic [i.e. adult] and control groups [P=0.030]. Additionally, the MT-ATP8 expression was significantly decreased in classic [P=0.004] and non-classic [i.e. infant] patients [P=0.013]. In total, 22 variants were observed in Cytochrome C oxidase, five of which were nonsynonymous, one leading to a stop codon and another [C9227G] being a novel heteroplasmic variant. The A8302G in the lysine tRNA gene was found in two brothers in a pedigree, while a T7572C variant in the aspartate tRNA gene was observed in two brothers in another pedigree

Conclusion: The extent of mitochondrial involvement in the classic group was more significant than in the non-classic form. Beside GAA deleterious mutations, it seems that mtDNA variants have a secondary effect on PD. Understanding, the role of mitochondria in the pathogenesis of Pompe may potentially be helpful in developing new therapeutic strategies

Assessment of bone morphogenetic protein 3 methylation in Iranian patients with colorectal cancer

Background: Colorectal cancer [CRC] is a common cancer that results in outstanding morbidity and mortality worldwide. DNA methylation is one of the most important epigenetic events that is thought to occur during the early stages of oncogenic transformation especially in CRC. The aim of this study was to investigate whether hypermethylation of bone morphogenetic protein 3 [BMP3] in tissue samples is implicated in Iranian patients with CRC

Methods: From fresh frozen tissue samples of 30 patients with CRC, the DNA was isolated, treated with sodium bisulfite and analyzed by methylation-specific polymerase chain reaction with primers specific for methylated or unmethylated promoter sequences of the BMP3 gene. Demographic characteristics of the patients including age, sex, tumor grade, location, stage, and TNM classification were evaluated and the relationship between hypermethylation of the gene and clinicopathological features was analyzed

Results: Methylation of the BMP3 promoter was often present in the DNA extracted from the tumoral tissues. A sensitivity of 56.66% and specificity of 93.3% were attained in the detection of colorectal neoplasia

Conclusion: We assumed that solely BMP3 methylation analysis in our population is not sufficient to select the gene as a screening biomarker and it should be considered in combination with other markers to screen for detection of colorectal cancer

Mitochondrial copy number and d-loop variants in Pompe patients

Objective: Pompe disease is a rare neuromuscular genetic disorder and is classified into two forms of early and late-onset. Over the past two decades, mitochondrial abnormalities have been recognized as an important contributor to an array of neuromuscular diseases. We therefore aimed to compare mitochondrial copy number and mitochondrial displacement-loop sequence variation in infantile and adult Pompe patients

Materials and Methods: in this retrospective study, the mitochondrial D-loop sequence was analyzed by polymerase chain reaction [PCR] and direct sequencing to detect possible variation in 28 Pompe patients [17 infants and 11 adults]. Results were compared with 100 healthy controls and sequences of all individuals were compared with the Cambridge reference sequence. Real-time PCR was used to quantify mitochondrial DNA copy number

Results: among 59 variants identified, 37[62.71%] were present in the infant group, 14[23.333%] in the adult group and 8[13.333%] in both groups. Mitochondrial copy number in infant patients was lower than adults [P<0.05]. A significant frequency difference was seen between the two groups for 12 single nucleotide polymorphism [SNP]. A novel insertion [317-318 ins CCC] was observed in patients and six SNPs were identified as neutral variants in controls. There was an inverse association between mitochondrial copy number and D-loop variant number [r=0.54]

Conclusion: the 317-318 ins CCC was detected as a new mitochondrial variant in Pompe patients

Investigation of PSEN1, 2 hot spots in Iranian early-onset Alzheimer's disease patients

Alzheimer's disease is a progressive, neurodegenerative disease with both genetic and non genetic causes. Familial Alzheimer's disease can be caused by mutations in the amyloid precursor protein, presenilin 1 and presenilin 2. Early-onset familial Alzheimer's disease [autosomal dominantly inherited] accounts for a small fraction [2-3%] of Alzheimer's disease cases. The aim of this study was investigation of exons 5, 7 in PSEN1 and exons 5, 6 in PSEN2 genes in Iranian patients with early onset Alzheimer disease. These exons were hot spots in different country. In this experimental study 24 patients with early onset Alzheimer disease and 48 healthy subjects as control group were included in this study. After DNAs extraction from whole blood, PCR-sequencing was used to amplify and analyze 4 exons. Two known mutations [Glu 120 Lys in exon 3 of two patients and Arg 62 His in exon 5 of one patient] were found. According to the above findings, these exons were not hot spot in Iran

Is Bax/Bcl-2 ratio considered as a prognostic marker with age and tumor location in colorectal cancer?

Bax and Bcl-2 are the major members of Bcl-2 family whose play a key role in tumor progression or inhibition of intrinsic apoptotic pathway triggered by mitochondrial dysfunction. Therefore, the balance between pro- and anti-apoptotic members of this family can determine the cellular fate. In this study, the relative level of mRNA expression of Bax and Bcl-2 genes was determined using RNA extraction, cDNA synthesis and RT-qPCR technique from 22 tumoral tissues and adjacent non-tumoral tissues from adenocarcinoma colorectal cancer. The potential prognostic and predictive significance of Bax and Bcl-2 gene expression and Bax/Bcl-2 ratio were demonstrated in colorectal cancer. The significant correlation between qPCR data and different clinicopathologic parameters of colorectal carcinoma, including age, gender, tumor size, tumor stage, tumor location, and tumor differentiation was also examined. Interestingly, no significant correlation was seen between Bax and Bcl-2 expressions and clinicopathological parameters of colorectal cancer. However, Bax/Bcl-2 ratio was statistically correlated with age and tumor location. Patients with age above 50 showed decreased levels of Bax/Bcl-2 ratio. Moreover, the Bax/Bcl-2 ratio was significantly lower in tumors resected from colon compared to sigmoid colon, rectosigmoid and rectum tumors. This study indicates a significant correlation between age and tumor location with Bax/Bcl-2 expression ratio, suggesting predictive value as a potential molecular marker of colorectal cancer

Molecular and clinical investigation of Iranian patients with Friedreich ataxia

Friedreich ataxia [FRDA] is an autosomal recessive disorder caused by guanine-adenine-adenine [GAA] triplet expansions in the FXN gene. Its product, frataxin, which severely reduces in FRDA patients, leads to oxidative damage in mitochondria. The purpose of this study was to evaluate the triple nucleotide repeated expansions in Iranian FRDA patients and to elucidate distinguishable FRDA clinical differences in these patients. A number of 22 Iranian patients [8 females and 14 males] from 16 unrelated families were studied. DNA was extracted from the peripheral blood of patients. The frequency and length of [GAA]n repeats in intron 1 of the FXN gene were analyzed using long-range PCR. In this study, the clinical criteria of FRDA in our patients and the variability in their clinical signs were also demonstrated. An inverse relationship was observed between GAA repeat size and the age of onset. Although some distinguishable clinical features [such as limb ataxia and lower limb areflexia] were found in our patients, 90-95% of them had extensor plantar response and dysarthria. The results showed only one positive diabetes patient and also different effects on eye movement abnormality among our patients. The onset age of symptoms showed a significant inverse correlation with allele size in our patients [P>0.05]. Based on comparisons of the clinical data of all patients, clinical presentation of FRDA in Iranian patients did not differ significantly from other FRDA patients previously reported

Three novel mutations in Iranian patients with Tay-Sachs disease

Tay-Sachs disease [TSD], or GM2 gangliosidosis, is a lethal autosomal recessive neurodegenerative disorder, which is caused by a deficiency of beta-hexosaminidase A [HEXA], resulting in lysosomal accumulation of GM2 ganglioside. The aim of this study was to identify the TSD-causing mutations in an Iranian population. In this study, we examined 31 patients for TSD-causing mutations using PCR, followed by restriction enzyme digestion. Molecular genetics analysis of DNA from 23 patients of TSD revealed mutations that has been previously reported, including four-base duplications c.1274_1277dupTATC in exon 11 and IVS2+1G>A, deletion TTAGGCAAGGGC in exon 10 as well as a few novel mutations, including C331G, which altered Gln>Glu in HEXB, A>G, T>C, and p.R510X in exon 14, which predicted a termination codon or nonsense mutation. In conclusion, with the discovery of these novel mutations, the genotypic spectrum of Iranian patients with TSD disease has been extended and could facilitate definition of disease-related mutations

Alexander disease: report of two unrelated infantile form cases, identified by GFAP mutation analysis and review of literature; the first report from Iran

Alexander disease [AD] is a sporadic leukodystrophy that predominantly affects infants and children and usually results in death within ten years after onset. The infantile form comprises the most of affected individuals. It presents in the first two years of life, typically with progressive psychomotor retardation with loss of developmental milestones, megalencephaly and frontal bossing, seizures, pyramidal signs and ataxia. The diagnosis is based on magnetic resonance imaging [MRI] findings and confirmed by GFAP gene molecular testing. GFAP gene encodes glial fibrillary acidic protein, is the only gene in which mutation is currently known to cause AD which is inherited in autosomal dominant manner. In this article we report the first two Iranian cases of infantile AD and their clinical, brain MRI and molecular findings. We report two novel mutations too in the GFAP gene that are associated with infantile form of AD. GFAP gene mutations are a reliable marker for infantile AD diagnosed according to clinical and MRI defined criteria. A genotype-phenotype correlation had been discerned for the two most frequently reported GFAP gene mutations in infantile type of AD [R79 and R239], with the phenotype of the R79 mutations appearing much less severe than that of the R239 mutations. Our findings confirm this theory

Association of mtDNA mutation with autism in Iranian patients

The autism spectrum disorders [ASD] are amongst the most heritable complex disorders. Although there have been many efforts to locate the genes associated with ASD risk, many has been remained to be disclosed about the genetics of ASD. Scrutiny's have only disclosed a small number of de novo and inherited variants significantly associated with susceptibility to ASD. These only comprise a small number of total genetic risk factors. Some studies confirm the contribution of mitochondrial genome mutations to the pathophysiology of the autism, but some other studies rejected such a contribution. In the current study we tried to scrutinize the association between mitochondrial tRNA genes mutations and the risk of Autism. DNA was extracted from the blood of 24 patients with ASD and 40 age-matched healthy controls from Special Medical Center in Tehran. 22 tRNA genes of mitochondrial genome were PCR amplified using 12 primer pairs and sequenced. Sequencing results were searched for mutations using clustalW Progran and then the association of mutations with the autism risk was assessed by statistical analysis using SPSS version 15. Many of the observed mutations were sporadic mutations without any significant relationship with the risk of autism, and the other mutations including those of high frequency showed no significant relationship with the risk of disease as well [P>0.05] except mutations 16126T>C [P=0.01], 14569G>A[P=0.02] and 1811A>G[P=0.04]. These three mutations were in the noncoding regions of the mitochondrial genome near tRNA genes. The mutation 16126T>C was in the mtDNA control region. Our study showed a significant relationship between the point mutations 16126T>C, 14569G>A and 1811A>G of the mitochondrial genome and the risk of autism

novel mutation in the aprataxin [APTX] gene in an Iranian individual suffering early-onset ataxia with oculomotor apraxia type 1[AOA1] disease

Ataxia with oculomotor apraxia type 1 [AOA1] shows early onset with autosomal recessive inheritance and is caused by a mutation in the aprataxin [APTX] gene encoding for the APTX protein. In this study, a 7-year-old girl born of a first-cousin consanguineous marriage was described with early-onset progressive ataxia and AOA, with increased cholesterol concentration and decreased albumin concentration in serum. PCR and direct DNA sequencing was performed after DNA extraction. Sequencing analysis revealed a novel homozygous deletion in c.643 and A>T single nucleotide polymorphism in c.641 in exon 6 of the APTX gene [ENST00000379825]. It seems that this region of exon 6 is probably a hot spot; however, no deletions have been reported in exon 6 yet

Study of FRDA gene in suspect Friedreich ataxia patients

Friedreich ataxia [FA] is an autosomal recessive disorder. Cause of about 2-4% of disease is a GAA triplet repeat expansion in the one allele and carries a point mutation as the other allele. This study was performed to investigate exons of FXN gene to find point mutations for the first time in Iran. In this descriptive study, 50 patients suspected to FA who referred to Special Medical Center were investigated. Genomic DNA was investigated by different PCR methods, including PCR for intron, Long PCR and PCR for exons of FXN gene. Then, products were sequenced and finally sequences were analyzed by related software. C to G nucleotide in intron 2 nt:825954, and T to C in intron 3 nt:832729 of FRDA gene were observed by sequencing method. Nucleotide G insertion was detected in exon 5a nt: 822225. Our study showed that diagnosis of FA is not simple because of clinical overlapping with other ataxia, some mutations in intron maybe affect on the disease which need more examination, and because of consanguinity marriage in Iran, some patients with homozygote mutation may show FA phenotype

Identification of a novel arylsulfatase b gene mutation in three unrelated Iranian mucopolysaccharidosis type-vi patients with different phenotype severity

Mucopolysaccharidosis type-VI [MPS-VI], which is inherited as an autosomal recessive trait, results from the deficiency of N-acetylgalactosamine 4-sulfatase [arylsulfatase B] activity and the lysosomal accumulation of dermatan sulfate. In this study, ARSB mutation analysis was performed on three unrelated patients who were originally from the West Azerbaijan province of Iran. After PCR and direct DNA sequencing, DNA extraction was performed. Sequencing analysis revealed a novel homozygous missense mutation in the ARSB gene at c. 457A>G [p. D486V] in three unrelated Iranian MPS-VI patients with different phenotype severity. The mutation type in three patients was the same; probably, because of a foundation effect on their population

Investigation of the mitochondrial ATPase 6/8 and tRNALys genes mutations in Autism

Autism results from developmental factors that affect many or all functional brain systems. Brain is one of tissues which are crucially in need of adenosine triphos-phate [ATP]. Autism is noticeably affected by mitochondrial dysfunction which impairs energy metabolism. Considering mutations within ATPase 6, ATPase 8 and tRNALys genes, associated with different neural diseases, and the main role of ATPase 6/8 in energy generation, we decided to investigate mutations on these mtDNA-encoded genes to reveal their roles in autism pathogenesis. In this experimental study, mutation analysis for the mentioned genes were performed in a cohort of 24 unrelated patients with idiopathic autism by employing amplicon sequencing of mtDNA fragments. In this study, 12 patients [50%] showed point mutations that represent a significant correlation between autism and mtDNA variations. Most of the identified substitutions [55.55%] were observed on MT-ATP6, altering some conserved amino acids to other ones which could potentially affect ATPase 6 function. Mutations causing amino acid replacement denote involvement of mtDNA genes, especially ATPase 6 in autism pathogenesis. MtDNA mutations in relation with autism could be remarkable to realize an understandable mechanism of pathogenesis in order to achieve therapeutic solutions

anticipation and inheritance pattern of c.487 A>G mutation in the GJB2 gene

Mutations in the GJB2 gene are the most common causes of hereditary hearing loss. This study reveals some facts about the inheritance pattern of M163V in the GJB2 gene. This study was performed on two different families with non-syndromic hearing loss. We screened the GJB2 coding region with direct sequencing. There was a substitution of A to G in exon 2 at nucleotide 487 [M163V]. This mutation was heterozygous in fathers and children while mothers were normal. Fathers of both families showed late onset hearing impairment, but there was early onset hearing loss in the children, which was more severe compared to the fathers. M163V has been reported as an unknown heterozygous mutation that leads to failure of the homotypic junctional channel formation. Another mutation in this codon is M163L, with an autosomal dominant inheritance, which impairs trafficking through the plasma membrane, resulting in cell death. Assessment of the familial pedigree has revealed anticipation in phenotype and autosomal dominant inheritance. These data in addition to the high conservation of methionine residue in mammalian species suggest that M163V is inherited with an autosomal dominant pattern. Therefore, the risk of inheritance will increase. Genetic counselors and otologists should prioritize the evaluation and prevention of this disorder in patients

Increased Prevalence 12308 A > G mutation in Mitochondrial tRNA[Leu [CUN]] Gene Associated with earlier Age of Onset in Friedreich Ataxia

Friedreich ataxia [FRDA] is an inherited recessive disorder. Mitochondrial DNA is a candidate modifying factor for FRDA.The purpose of this study was to investigate the relationship between the tRNA[Leu [CUN]] 12308 A> G mutation and age of onset in Friedreich ataxia. The 12308 A> G substitution in mitochondrial tRNA[Leu [CUN]] was examined in DNA samples from 30 Friedreich ataxia patients and 48 control subjects by temporal temperature gradient gel electrophoresis [TTGE] and sequencing. Logistic regression was used to determine of cutoff age of onset. Twenty-two patients had the 12308 A> G mutation, and we found that its overall prevalence was significantly higher in 20 patients aged 17 years or younger than in 2 patients aged over 17 years [90% versus 10%]. The 12308 A> G mutation lies in a region that has been highly conserved between species. Our results show that the 12308 A > G mutation is associated with earlier age of onset in Friedreich ataxia. Thus, this mutation might cause the younger age of onset in FRDA

L-2-hydroxyglutaric aciduria is a diagnostic indicator of leukodystrophy: a case report

L-2-Hydroxyglutaric aciduria is a rare autosomal recessive inherited neurometabolic disorder.It is characterized by slow progressive neurological dysfunction with cerebellar ataxia, pyramidal and extrapyramidal signs, intellectual decline, and seizures. Herein, we report a case of a 7-year-old boy from Tehran whose symptoms and signs indicated leukoencephalopathy with macrocephaly and motor delay

IL7R and rag1/2 Genes mutations/polymorphisms in patients SCID

SCID disorder is major failure of the immune system, usually genetic. The aim of this study was on mutations detection of RAG1, RAG2, and IL7RG genes in SCID cases. Mutation detection was performed by PCR sequencing. Our results indicated that 13 mutations were found through cases which include 4 mutations in IL7R gene [T661I, I138V, T56A, C57W], 7 mutations in RAG1 [W896X, W204R, M324V, T731I, Ml006V, K820R, and R249H], and 2 mutations in RAG2 gene [R229W, deltaT251]

Effects of growth hormone on muscle strength, tone and mobility of children with Prader-Willi syndrome

Prader-Willi Syndrome [PWS] is a genetic syndrome presenting with severe hypotonia and decreased agility. Growth Hormone [GH], which is often used in these patients to treat short stature and obesity, seems improve hypotonia, physical strength, activity, and locomotor developmental ability. The aim of this study was to find the effects of growth hormone on agility and strength of these patients. In a prospective randomized controlled clinical trial in an out-patient pediatric endocrine clinic in Tehran, 21 PWS children [12 boys and 9 girls, 4 to 9 years old] were divided into either GH-treated or control groups and followed for two years. Agility run, sit ups, weight lifting, and inspiratory and expiratory strength were considered as the main outcome measures. All the outcome measures of the GH treated group showed a significant improvement compared to the control group. GH causes a significant improvement in agility and strength of PWS children

report of two cases of TGM1 mutations in Iranian patients with lamellar ichthyosis

Autosomal Recessive Congenital Ichthyosis [ARCI] is a rare, heterogenous keratinization disorder of the skin, classically divided into two clinical subtypes, Lamellar Ichthyosis [LI] and Nonbullous Congenital Ichthyosi-formis Erythroderma [NCIE]. Lamellar Ichtyosis is caused by mutations in the TGM1 gene that encodes transglutaminase 1 enzyme, which is critical for the assembly of the cornified cell envelope in terminally differentiating keratinocytes. TGM1 is a complex enzyme existing as both cytosolic and membrane-bound forms. Moreover, TGM1 is proteolytically processed, and the major functionally active form consists of a membrane-bound 67/33/10-kDa complex with a myristoylated and palmitoylated amino-terminal 10-kDa membrane anchorage fragment. In this study, all 14 coding exons of TGM1 gene were investigated using PCR-sequencing method in three Iranian patients with different phenotypes which are often caused by homozygote or compound heterozygote mutations and a homozygote mutation [G218S] in exon 4 and three heterozygote mutations [R37K, D58N, D86N] in exon 2 were observed. The mutation [D86N] was seen in two patients simultaneously