Association of ACE and MTHFR genetic polymorphisms with type 2 diabetes mellitus: Susceptibility and complications

HYPOTHESIS/INTRODUCTION

Polymorphisms of angiotensin converting enzyme (ACE) and methylene-tetrahydrofolate reductase (MTHFR) genes have been proposed to be associated with type 2 diabetes mellitus (T2DM) with conflicting results. This work was planned in order to check for the association of these polymorphisms with the susceptibility for and complications of T2DM among Egyptian cases.

MATERIALS AND METHODS

This is a case controlled study involving 203 patients with T2DM and 311 healthy controls. Polymorphic variants of ACE I>D and MTHFR (677 C>T and 1298 A>C) were determined using the polymerase chain reaction (PCR) restriction analysis technique.

RESULTS

The susceptibility to T2DM was higher among subjects having the MTHFR 677TT (odds ratio (OR)=2.2, p=0.01), MTHFR 1298 AA (OR=1.84, p=0.001) and ACE (ID+II) (OR=2.0, p=0.0007) genotypes. Logistic regression analysis showed that MTHFR 677T allele was a risk factor for diabetic retinopathy (DR) (OR=3.47, p<0.001), diabetic polyneuropathy (DPN) (OR=5.2, p<0.0001) and ischemic heart disease (IHD) (OR=2.9, p<0.05), while MTHFR 1298 C allele was a risk factor for DR (OR=4.2, p<0.001) and the ACE DD genotype was a risk factor for DPN (OR=3.1, p<0.001).

CONCLUSIONS

The MTHFR 677 TT genotype was associated with T2DM susceptibility and complications (DR, DPN and IHD). The MTHFR 1298 CC, AC and ACE DD genotypes were associated with DR and DPN.

ACE I/D and eNOS E298D gene polymorphisms in Saudi subjects with hypertension

BACKGROUND

Hypertension has a multifactorial background based on genetic and environmental interactive factors.

OBJECTIVES

We aimed to test for the association of the angiotensin-converting enzyme (ACE) and endothelial nitric oxide synthase (eNOS) gene polymorphisms with hypertension.

SUBJECTS AND METHODS

Participants included 120 Saudi patients with hypertension and 250 normal healthy controls. For all participants, DNA was processed for characterization of ACE I/D and eNOS E298D gene polymorphisms.

RESULTS

Hypertensive cases showed a significantly higher frequency of the ACE mutant D allele carriage (98.3% vs. 92.4%, p = 0.028, OR = 4.8). Cases with hypertension associated with diabetes and obesity showed 100% mutant D allele carriage. Regarding the eNOS E298D polymorphism, the frequency of the mutant D allele carriage was only observed to be higher among cases with hypertension associated with diabetes and obesity, in comparison with controls, yet not reaching statistical significance (41.2% vs. 34%, p > 0.05).

CONCLUSIONS

There is increased frequency of ACE and eNOS mutant allele carriage among Saudi patients affected with hypertension, particularly if accompanied by obesity and diabetes.

Methylene tetrahydrofolate reductase and angiotensin converting enzyme gene polymorphisms related to overweight/obesity among Saudi subjects from Qassim Region

Background: This work was planned to check for the association of polymorphisms related to methylenetetrahydrofolate reductase (MTHFR) and angiotensin converting enzyme (ACE) genes with overweight/obesity among Saudi subjects from Qassim region.

Methods: This work included 130 subjects having overweight or obesity and 111 normal controls. Their age mean ± SD was 27 ± 9.8 and 24 ± 8.8 years respectively. Their DNA was analyzed for polymorphisms of MTHFR; 677C/T and 1298 A/C and ACE; I/D genes using real-time PCR.

Results: Genotype and allele frequencies of studied polymorphisms in cases of overweight/obesity showed no significant statistical difference compared to that of controls. However, on analysis of body mass index (BMI), cases showed slightly higher but statistically nonsignificant mean ± SD values among those carrying the mutant MTHFR 677 T allele (CT + TT vs. CC, 30.7 ± 4.5 vs. 29.9 ± 4.9), 1298 C allele (AC + CC vs. AA, 29.9 ± 4.1 vs. 29.7 ± 5.5) and ACE D allele (ID + DD vs. II, 30.0 ± 5.1 vs. 29.1 ± 2.8). In addition controls having the DD and ID genotypes showed higher statistically significant values of BMI than those of the II genotype (22.0 ± 1.9, 21.7 ± 2.6 and 19.5 ± 2.3 respectively, p < 0.05).

Conclusion: There is no solid association of polymorphisms related to MTHFR and ACE genes with non-complicated overweight or obesity among Saudi subjects from Qassim Region.

Association of cytokine gene polymorphisms with psoriasis in cases from the Nile Delta of Egypt

BACKGROUND

Psoriasis is a chronic inflammatory skin disease with an immunogenetic background. This study was planned to check for the association of polymorphisms related to cytokine genes TNF-alpha-308(G/A), IL-10-1082(G/A), IL-6-174(G/C), and IL-1Ra (VNTR) with psoriasis in cases from Egypt.

METHODS

This study included 46 cases with psoriasis recruited from the Department of Dermatology, University Hospitals, Nile Delta region of Egypt. They included 14 males and 32 females with a mean age +/- SD of 46.68 +/- 12.16 years and a range of 15 to 70 years. Their genotypes were compared to 98 healthy controls of matched age and sex from the same locality. Genotyping was done through DNA amplification using PCR with sequence-specific primers for polymorphic alleles.

RESULTS

Compared to controls, cases showed a significantly higher frequency of certain genotypes including IL-6-174 CC (p < 0.001, OR = 6.7), IL-10-1082 GG (p < 0.05, OR = 5.1), and TNF-alpha-308 GG (p < 0.05, OR = 3.7). Combined heterozygosity for IL-10 GA, IL-6 GC, and TNF GA showed a significant low frequency among the cases studied.

CONCLUSION

Genetic polymorphisms related to the IL6, IL10, and TNF-alpha genes showed a particular pattern of association with psoriasis that may have a potential impact on disease counseling and management.

Gene polymorphisms of TNF-alpha-308 (G/A), IL-10(-1082) (G/A), IL-6(-174) (G/C) and IL-1Ra (VNTR) in Egyptian cases with type 1 diabetes mellitus

BACKGROUND

Type 1 diabetes (T1D) is a genetically conditioned autoimmune disease in which cytokines play an important role. Objectives. To check for the association of polymorphisms of cytokine genes with type 1 diabetes. Subjects. This work included 50 cases with T1D and 98 healthy individuals from the Nile Delta region of Egypt. Cases included 20 males and 30 females with a median age of 25 and range of 15-50 years.

METHODS

DNA was amplified using PCR with sequence-specific primers for detection of polymorphisms related to tumor necrosis factor (TNF)-alpha(- 308) (G/A), interleukin (IL)-10(- 1082) (G/A), IL-6(- 174) (G/C), and IL-1Ra (VNTR).

RESULTS

Cases with T1D showed significant higher frequency of genotypes of TNF-alpha(- 308) AA (p < 0.001, odds ratio (OR) = 7.91), IL-6-17CC (p < 0.05, OR = 3.36) and IL-1Ra A1A1 (p < 0.05, OR = 3.68) with significant lower frequencies of TNF-alpha(- 308) GA, and IL-1Ra A1A2 genotypes (p < 0.001 and < 0.05, respectively). They also showed significant higher frequency of TNF-alpha(- 308) allele A (p < 0.05, OR = 2.0), IL-1Ra allele A1 (p < 0.05, OR = 2.98) with a significant lower frequency of TNF-alpha(- 308) G allele and IL-1Ra A2 allele (p < 0.05). No significant difference was detected among cases in relation to IL-10(- 1082) (G/A) genotypes or alleles nor in relation to age, sex, consanguinity or family history of the disease.

CONCLUSIONS

Polymorphisms related to TNF-alpha and IL-1Ra genes may be considered genetic markers for T1D among Egyptians with a potential impact on family counseling and management.

Dysmorphic Features, Consanguinity and Cytogenetic Pattern of Congenital Heart Diseases: a pilot study from Mansoura Locality, Egypt

BACKGROUND

Congenital heart diseases (CHD) constitute a common cause of birth defects with a multifactorial inheritance background.

OBJECTIVES

to check for the dysmorphic features, consanguinity and cytogenetic pattern that may be associated with congenital heart disease in Egyptian cases from Mansoura, Egypt.

METHODS

This work is a pilot prospective controlled study including randomly selected 69 cases affected with congenital heart disease recruited from the Pediatric Cardiology Department, Mansoura University, Egypt. These cases were compared to 500 normal children of matched age and sex taken from the same locality serving as a control group. Complete history taking, clinical examination for dysmorphic features as well as cardiac examination were carried out for all subjects. Furthermore, cases were evaluated by Echocardiography and cytogenetic studies.

RESULTS

Egyptian children affected with CHD were significantly associated with positive family history of CHD, perinatal history of maternal diseases or drug intake during pregnancy and positive parental consanguinity (odds ratio = 10.5, 7.6 and 3.1 respectively). Significant associated dysmorphic features included ear anomalies, eye anomalies, cleft lip, polydactyly and cleft palate (odds ratio = 217.6, 176.6, 68.7 and 37.07 respectively). Seven cases (10.1%) had chromosomal aberrations and were associated with dysmorphic features.

CONCLUSION

Risk of CHD increased with positive family history and consanguinity. Cytogenetic studies added to dysmorphic features seem to have an important clue for early diagnosis of CHD. Key words: Heart disease, risk factors, dysmorphism, Egypt.

Rapid sex determination using PCR technique compared to classic cytogenetics

BACKGROUND

Fetal sexual differentiation relies on the translation of chromosomal sex established at fertilization into gonadal sex and somatic sex as development proceeds. In cases where chromosomal, gonadal, and somatic sex are incongruent in human infants and children, rapid establishment of the diagnosis and implementation of medical and surgical management is of paramount importance, since the gender identity is so important to the psychological well-being throughout life.

OBJECTIVE

This work was done in order to test the value of PCR technique for rapid sex determination compared to classic cytogenetic technique.

METHODS

Subjects included 20, cases including 10 neonates with ambiguous genitalia, 2 adult females with delayed puberty and 8 adult males with infertility, in addition to 20 normal infants of both sexes as a control group. The diagnosis of sex was attempted through examination, cytogenetic study, ultrasonography, gonadal biopsy and hormonal analysis, in addition to PCR amplification for the detection of SRY and ATL1 gene loci on Y and X chromosomes respectively.

RESULTS

Four neonates were diagnosed as partial testicular feminization showed both positive bands for the Y and X chromosomes and a karyogram of 46/XY. Three neonates were diagnosed as true hermaphrodites showed positive amplification for both Y and X chromosomes with a mosaic karyogram 46,XX/XY. Three neonates were diagnosed as cases of adrenogenital syndrome showed positive amplification of only the Xchromosome and had a karyogram of 46/XX. One of the two adult females was diagnosed as turner syndrome showed positive amplification of the X chromosome and a karyogram of 45/XO; the other one was diagnosed as complete testicular feminization had a positive amplification of X and Y chromosomes and a karyogram of 46/XY. The 8 adult males with infertility showed a positive amplification of X and Y chromosome and a karyogram of 47/XXY (Klinefelter syndrome) in 7 cases and 46/XY gonadal dysgenesis in one case.

CONCLUSION

We concluded that PCR as a simple, rapid and reliable technique can complement and also confirm cytogenetic studies in the diagnosis of sex in cases of sex chromosome disorders.

Gene polymorphisms of TNF-alpha(-308), IL-10(-1082), IL-6(-174), and IL-1Ra(VNTR) related to susceptibility and severity of rheumatic heart disease

Rheumatic heart disease (RHD) is an inflammatory disease of the heart tissues caused by interactive immune, genetic, and environmental factors. The objective of this study is to test for the association of polymorphisms related to cytokine genes with susceptibility and severity of RHD among affected children from the Nile Delta region of Egypt. The study included 50 children with chronic RHD (29 males and 21 females), with a mean age of 12.2 years, in addition to 98 healthy unrelated controls. Cases were further classified on the basis of echocardiographic findings into those with only mitral valve disease (MVD) or multivalvular lesions (MVLs) and also as mild, moderate, or severe valve lesions. For all cases and controls, DNA was extracted and amplified using polymerase chain reaction with sequence-specific primers for detection of single nucleotide polymorphisms (SNPs) in the promoter regions of cytokine genes tumor necrosis factor (TNF)-alpha(-308 )G/A, interleukin (IL)-10(-1082 )G/A, and IL-6(-174 )G/C as well as a variable number of tandem repeats (VNTRs) in intron 2 of the IL-1Ra gene. All cases showed a significantly higher frequency of homozygous genotypes of TNF-alpha(-308 )A/A [odds ratio (OR) = 5.7, p < 0.001], IL-10(-1082) A/A (OR = 3.1, p < 0.05), IL-10(-1082) G/G (OR = 5.2, p < 0.05), and IL-1Ra A1/A1 (OR = 2.2, p < 0.05). Cases with MVD showed higher frequencies of genotypes TNF-alpha(-308 )A/A, G/G; IL-10(-1082) G/G; and IL-1Ra(VNTR) A1/A1 (p < 0.05). Cases with MVL showed a significantly higher frequency of homozygous A/A genotype of both TNF-alpha(-308 )(OR = 10.6, p < 0.05) and IL-10(-1082) (OR = 5.2, p < 0.05). The same was observed for cases with severe valve lesions. On the other hand, all studied groups showed significantly lower frequency of heterozygous genotypes of TNF-alpha(-308 )G/A, IL-10(-1082) G/A, and IL-1Ra(VNTR) A1/A2. No significant difference was found regarding the frequency of IL-6(-174 )G/C polymorphisms in total cases or subgroups compared to controls (p > 0.05). Predisposition to RHD is influenced by genetic factors including cytokine gene polymorphisms, with possible susceptibility to severe disease with multivalvular affection among cases with composite polymorphism (TNF-alpha(-308 )A/A and IL-10(-1082) A/A) and (TNF-alpha(-308 )A/A and IL-10(-1082) G/G).

Clinical and molecular diagnosis of Familial Mediterranean Fever in Egyptian children

BACKGROUND

Familial Mediterranean Fever (FMF) is an autosomal inherited disorder affecting certain races including Arabs. Diagnosis depends mainly on clinical basis, but mild forms may remain undiagnosed.

OBJECTIVES

This study aims at an accurate diagnosis of FMF in Egyptian children by detection of genetic mutations in addition to clinical assessment.

SUBJECTS AND METHODS

Subjects included 66 Egyptian cases (37 males and 29 females) with a mean age of onset of 6.9 years. They had been referred from health centers and hospitals of the Delta region, Egypt. Analysis of the clinical manifestations was performed using Tel-Hashomer criteria in addition to 10 items clinical score system. For all these cases, DNA analysis was made for three common mutations M680I, M694V, and V726A using amplification refractory mutation system (ARMS-PCR) technique.

RESULTS

Most of the cases had attacks ranging from 3-5 days duration with the mean of 3.6 days. Their rate of recurrence was variable but 47 % of them had suffered attacks 10-30 times/year. Abdominal pain was the most common symptom (87.9%) followed by fever (82%), arthritis or arthralgia (56.1%), chest pain (45%) and myalgia (6%). Laparotomy had been done during attacks for exploration or appen-dectomy in 27.7% of cases. Positive mutations were detected among 42 cases (63.6%), of them 14 (21.2%) were compound heterozygotes, 7 (10.6%) were had homozygotes while 21 (31.8%) were simple heterozygotes. Allele M694V was the most frequent one (18.8%) followed by V726A (17.4%) and M680I (12.1%). Taking positive mutation as a guide for diagnosis, a cutoff clinical score level was determined with =15 for unlikely, =20 for definite and 15-20 for probable diagnosis.

CONCLUSION

Diagnosis of FMF among Egyptian children cases although based mainly on clinical suspicion requires to be confirmed through detection of the corresponding mutation which can be easily made using the simple ARMS-PCR technique.

Molecular analysis of A1AT (S and Z) and HFE (C282Y and H63D) gene mutations in Egyptian cases with HCV liver cirrhosis

BACKGROUND

Alpha-1-antitrypsin (A1AT) S and Z deficiency alleles and hemochromatosis (HFE) mutant C282Y, H63D alleles were reported to potentially affect the liver even if present in a heterozygous state.

OBJECTIVES

This is a cross-sectional, randomized, case controlled study for evaluation of the frequency of these alleles in Egyptian patients with HCV liver cirrhosis and of their association with the disease.

SUBJECTS

This study included 48 cases with viral C cirrhosis recruited from the Hepatology Unit, Mansoura University Hospital, Egypt, and 70 unrelated healthy controls.

METHODS

PCR amplification of relevant gene segment followed by restriction enzyme digestion Taq1 for detection of A1AT gene S and Z alleles, digestion with Rsa I and Bcl I for HFE gene C282Y and H63D alleles. These alleles were then characterized through analysis of resulting restriction fragment length polymorphism (RFLP).

RESULTS

Both heterozygous (MS) and homozygous (SS) genotypes were significantly more frequent in cases than in controls ( P<0.05, RR= 2.23 and 2.17 respectively). Gene frequency of S allele was higher in cases than controls (P<0.05, RR=2.17). Homozygosity (ZZ) genotype, present only in cases (6.3% vs 0.0% in controls,) did not reach statistical significance. HFE gene heterozygosity for H63D allele was detected in 20.0% of cases and 21.4% of controls, whereas C282Y allele was detected neither among cases nor in controls.

CONCLUSION

The presence of the relatively high frequency of A1AT S and HFE H63D allele carriers in Egyptian cases of HCV liver cirrhosis suggest the necessity to implement routine molecular analysis of these genes for detection of risk genotypes among affected families.