Artificial Intelligence-Assisted Meta-Analysis of the Frequency of ACE I/D Polymorphisms in Centenarians and Other Long-Lived Individuals

Current research on the angiotensin-converting-enzyme (ACE) gene has yielded controversial results on whether different ACE polymorphisms are linked with human longevity. ACE polymorphisms are a risk factor for Alzheimer's disease and age-onset diseases that may contribute to the mortality of older people. Our goal is to consolidate existing studies, using artificial intelligence-assisted software to come to a more precise understanding of the role of the ACE gene in human longevity. The I (insertion) and D (deletion) polymorphisms in the intron are correlated with the levels of circulating ACE; homozygous D (DD) is high, and homozygous I (II) is low. Here, we performed a detailed meta-analysis of the I and D polymorphisms using centenarians (100+ years old), long-lived subjects (85+ years old), and control groups. ACE genotype distribution was analyzed across a total of 2054 centenarians and 12,074 controls, as well as 1367 long-lived subjects between the ages of 85-99, using the inverse variance and random effects methods. The ACE DD genotype was found to be favored in centenarians (OR: 1.41 (95% CI: 1.19-1.67), p < 0.0001) with a heterogeneity of 32%, and the II genotype slightly favored the control groups (OR: 0.81 (95% CI: 0.66-0.98), p = 0.03) with a heterogeneity of 28%, corroborating results from previous meta-analyses. Novel to our meta-analysis, the ID genotype was found to be favored in control groups (OR: 0.86 (95% CI: 0.76-0.97), p = 0.01) with a heterogeneity of 0%. The long-lived group showed a similar positive association between the DD genotype and longevity (OR: 1.34 (95% CI: 1.21-1.48), p < 0.0001) and a negative association between the II genotype and longevity (OR: 0.79 (95% CI: 0.70-0.88), p < 0.0001). The long-lived ID genotype did not show significant findings (OR: 0.93 (95% CI: 0.84-1.02), p = 0.79). In conclusion, the results suggest a significant positive association of the DD genotype with human longevity. However, despite the previous study, the results do not confirm a positive association of the ID genotype with human longevity. We suggest a few important paradoxical implications: (1) inhibition of ACE can increase longevity in model systems from nematodes to mammals, seemingly opposite to the finding in humans; (2) exceptional longevity associated with homozygous DD is also associated with age-related diseases with higher mortality risks in homozygous DD. We discuss ACE, longevity, and age-related diseases.

Angiotensin-converting enzyme gene polymorphism and digestive system cancer risk: A meta-analysis based on 9656 subjects

The angiotensin-converting enzyme (ACE) is the major regulator of the renin-angiotensin system, and it has been reported that genetic polymorphisms at this locus are associated with risk in numerous types of human cancers. In the current meta-analysis, we aimed to evaluate the association between the ACE Gene insertion/deletion (I/D) polymorphism (DD vs II) and digestive system cancer susceptibility. A total of 19 case-control studies among 3722 patients with seven different types of cancer were included in this meta-analysis. In the pooled analysis, the relationship between the ACE I/D polymorphism and digestive system cancer risk was not statistically significant (odds ratio [OR], 0.93; 95% confidence interval [CI], 0.68-1.29; P = 0.65; random model). Furthermore, subgroup analyses by cancer type also did not reveal an association between ACE polymorphisms and colorectal cancer (OR, 1.14; 95% CI, 0.823-1.58; P = 0.43; random effect model) and gastric cancer (OR, 0.79; 95% CI, 0.51-1.22; P = 0.28; random effect model). These findings indicate that ACE polymorphisms in the digestive tract may still affect the survival of cancer patients, and future studies into the topic of effect of ACE on cancer prognosis are warranted.

Review and meta-analysis of genetic polymorphisms associated with exceptional human longevity

BACKGROUND

Many factors contribute to exceptional longevity, with genetics playing a significant role. However, to date, genetic studies examining exceptional longevity have been inconclusive. This comprehensive review seeks to determine the genetic variants associated with exceptional longevity by undertaking meta-analyses.

METHODS

Meta-analyses of genetic polymorphisms previously associated with exceptional longevity (85+) were undertaken. For each variant, meta-analyses were performed if there were data from at least three independent studies available, including two unpublished additional cohorts.

RESULTS

Five polymorphisms, ACE rs4340, APOE ε2/3/4, FOXO3A rs2802292, KLOTHO KL-VS and IL6 rs1800795 were significantly associated with exceptional longevity, with the pooled effect sizes (odds ratios) ranging from 0.42 (APOE ε4) to 1.45 (FOXO3A males).

CONCLUSION

In general, the observed modest effect sizes of the significant variants suggest many genes of small influence play a role in exceptional longevity, which is consistent with results for other polygenic traits. Our results also suggest that genes related to cardiovascular health may be implicated in exceptional longevity. Future studies should examine the roles of gender and ethnicity and carefully consider study design, including the selection of appropriate controls.

Angiotensin-Converting Enzyme ID Polymorphism in Patients with Heart Failure Secondary to Chagas Disease

Background

Changes in the angiotensin-converting enzyme (ACE) gene may contribute to the increase in blood pressure and consequently to the onset of heart failure (HF). The role of polymorphism is very controversial, and its identification in patients with HF secondary to Chagas disease in the Brazilian population is required.

Objective

To determine ACE polymorphism in patients with HF secondary to Chagas disease and patients with Chagas disease without systolic dysfunction, and to evaluate the relationship of the ACE polymorphism with different clinical variables.

Methods

This was a comparative clinical study with 193 participants, 103 of them with HF secondary to Chagas disease and 90 with Chagas disease without systolic dysfunction. All patients attended the outpatient department of the General Hospital of the Federal University of Goias general hospital. Alleles I and D of ACE polymorphism were identified by polymerase chain reaction of the respective intron 16 fragments in the ACE gene and visualized by electrophoresis.

Results

In the group of HF patients, 63% were male, whereas 53.6% of patients with Chagas disease without systolic dysfunction were female (p = 0,001). The time from diagnosis varied from 1 to 50 years. Distribution of DD, ID and II genotypes was similar between the two groups, without statistical significance (p = 0,692). There was no difference in clinical characteristics or I/D genotypes between the groups. Age was significantly different between the groups (p = 0,001), and mean age of patients with HF was 62.5 years.

Conclusion

No differences were observed in the distribution of (Insertion/Deletion) genotype frequencies of ACE polymorphism between the studied groups. The use of this genetic biomarker was not useful in detecting a possible relationship between ACE polymorphism and clinical manifestations in HF secondary to Chagas disease.

Demographics, phenotypic health characteristics and genetic analysis of centenarians in China

After a brief introduction to the background, significance and unique features of the centenarian population in China, we describe the Chinese Longitudinal Healthy Longevity Study (CLHLS), which is the world's largest study of centenarians, nonagenarians, octogenarians, and compatible young-old aged 65-79. Based on the CLHLS data and other relevant studies, we summarize demographic and socioeconomic characteristics as well as self-reported and objectively-tested health indicators of centenarians in China, with an emphasis on gender differences and rural/urban disparities. We then compare five-year-age-specific trajectories of physical and cognitive functions, self-reported health, and life satisfactions from ages 65-69 to 100+, concluding that good psychological resilience and optimism are keys to the exceptional longevity enjoyed by centenarians. We discuss recent findings of novel loci and pathways that are significantly associated with longevity based on the genome-wide association study (GWAS) of the CLHLS centenarian sample, which is 2.7 times as large as prior GWAS of longevity. We also highlight colleagues' and our own studies on longevity candidate genes and gene-environment interaction analyses. Finally, we discuss limitations inherent in our studies of centenarians in China and further research perspectives.

The genetics of exceptional longevity: Insights from centenarians

As the world population ages, so the prevalence increases of individuals aged 100 years or more, known as centenarians. Reaching this age has been described as exceptional longevity (EL) and is attributed to both genetic and environmental factors. Many genetic variations known to affect life expectancy exist in centenarians. This review of studies conducted on centenarians and supercentenarians (older than 110 years) updates knowledge of the impacts on longevity of the twenty most widely investigated single nucleotide polymorphisms (SNPs).

We are ageing

Ageing and longevity is unquestioningly complex. Several thoughts and mechanisms of ageing such as pathways involved in oxidative stress, lipid and glucose metabolism, inflammation, DNA damage and repair, growth hormone axis and insulin-like growth factor (GH/IGF), and environmental exposure have been proposed. Also, some theories of ageing were introduced. To date, the most promising leads for longevity are caloric restriction, particularly target of rapamycin (TOR), sirtuins, hexarelin and hormetic responses. This review is an attempt to analyze the mechanisms and theories of ageing and achieving longevity.

The ACE DD genotype and D-allele are associated with exceptional longevity: a meta-analysis

The ACE I/D polymorphism has been associated with longevity, although not consistently. The objective of this study was to detect the possible unequal distribution of the alleles and genotypes of this polymorphism among centenarians and younger segments of the population. Relevant data were extracted from studies in the literature, comparing genotype and allele frequencies between centenarians and younger controls. The association of ACE I/D polymorphism with exceptional longevity was analyzed in a total of 1803 centenarians and 10,484 controls using the chi-square test with the Yates correction. We conducted combined analyses for all ethnic groups studied in the literature (Caucasian, Chinese and Korean) as well as for Caucasians only. The DD genotype (odds ratio (OR): 1.25 (95% confidence interval (CI): 1.02-1.54), P=0.032) and the D-allele were more frequent in Caucasian centenarians compared with their younger controls (OR: 1.16 (95% CI: 1.05-1.28), P<0.001). Similar findings were obtained when all ethnic origin groups were included in the analyses, with no evidence of publication bias or heterogeneity (P>0.05). The present meta-analysis indicates that the ACE D-allele and the DD genotype might confer a modest, albeit significant advantage to reach exceptional longevity.

Evidence from case-control and longitudinal studies supports associations of genetic variation in APOE, CETP, and IL6 with human longevity

In this study, we investigated 102 single-nucleotide polymorphisms (SNPs) covering the common genetic variation in 16 genes recurrently regarded as candidates for human longevity: APOE; ACE; CETP; HFE; IL6; IL6R; MTHFR; TGFB1; APOA4; APOC3; SIRTs 1, 3, 6; and HSPAs 1A, 1L, 14. In a case-control study of 1,089 oldest-old (ages 92-93) and 736 middle-aged Danes, the minor allele frequency (MAF) of rs769449 (APOE) was significantly decreased in the oldest-old, while the MAF of rs9923854 (CETP) was significantly enriched. These effects were supported when investigating 1,613 oldest-old (ages 95-110) and 1,104 middle-aged Germans. rs769449 was in modest linkage equilibrium (R (2)=0.55) with rs429358 of the APOE-ε4 haplotype and adjusting for rs429358 eliminated the association of rs769449, indicating that the association likely reflects the well-known effect of rs429358. Gene-based analysis confirmed the effects of variation in APOE and CETP and furthermore pointed to HSPA14 as a longevity gene. In a longitudinal study with 11 years of follow-up on survival in the oldest-old Danes, only one SNP, rs2069827 (IL6), was borderline significantly associated with survival from age 92 (P-corrected=0.064). This advantageous effect of the minor allele was supported when investigating a Dutch longitudinal cohort (N=563) of oldest-old (age 85+). Since rs2069827 was located in a putative transcription factor binding site, quantitative RNA expression studies were conducted. However, no difference in IL6 expression was observed between rs2069827 genotype groups. In conclusion, we here support and expand the evidence suggesting that genetic variation in APOE, CETP, and IL6, and possible HSPA14, is associated with human longevity.

The frequency of 4 common gene polymorphisms in nonagenarians, centenarians, and average life span individuals

Single nucleotide polymorphisms of angiotensin-converting enzyme (ACE) such as rs1799752, nuclear factor kappa B (NFkB) such as rs28362491 and cholesteryl ester transport protein (CETP) such as rs708272 (TaqB1) and rs5882 (I405V) were evaluated in nonagenarians, centenarians, and average life span individuals (controls). The study population (n = 307; 190 nonagenarians, 12 centenarians and 105 middle-aged controls) was genotyped for ACE, NFkB, and CETP genetic variants. The age of nonagenarian and centenarian group ranged between 90 and 111 years; centenarians and controls age ranged from 99 to 111, and from 18 to 80 years, respectively. The I carriers of ACE I/D gene were fewer in nonagenarians compared to centenarians (37.6% vs 62.5%, P = .016). The I carriers of ACE gene were more frequent in centenarians compared to controls (62% vs 41%, P = .045). No differences in frequency of common NFkB and CETP genotypes between patients with exceptional longevity and middle-aged patients were observed.

Ideal lipid profile and genes for an extended life span

PURPOSE OF REVIEW

The world population is aging and a rapid increase is being seen in the very elderly (aged >80 years). Cholesterol levels in general rise with age and high cholesterol has been associated with extreme longevity. The relationship between lipids and cardiovascular events in the extreme elderly is unclear.

RECENT FINDINGS

A number of genetic factors associated with lipid metabolism have also been described as having potential antiaging roles, including the genes encoding lipoprotein-associated factors - apolipoprotein E and cholesterol ester transfer protein; adipose tissue metabolism - adiponectin, leptin, glycaemia; and blood pressure - angiotensinogen. Clinical trials of lipid-lowering therapies have recruited subgroups of moderately elderly patients, but only the Prospective Study of Pravastatin in the Elderly at Risk (PROSPER) trial specifically recruited an elderly population. There is no direct equivalent of the Hypertension in the Very Elderly trial (HYVET) study of antihypertensive patients in the extreme elderly. No heterogeneity has been seen with the effects of statin therapy in the elderly compared with younger age groups on classical cardiovascular endpoints of coronary heart disease and stroke.

SUMMARY

The optimal cholesterol target, long-term tolerability and the specific effects of statins on other vascular-associated diseases of aging, for example arterial aneurysms, microvascular renal and cerebral disease (dementias), remain to be determined.

No association between ACE polymorphism and risk of nasopharyngeal carcinoma

Emerging evidence has shown that angiotensin I-converting enzyme (ACE) plays pivotal roles not only in the regulation of cardiovascular homeostasis but also in the process of tumorigenesis. A common ACE I/D polymorphism has been found to be functional, with the D allele displaying a higher plasma ACE level and ACE activity. The purpose of this study was to investigate whether the ACE I/D polymorphism was related to the risk of nasopharyngeal carcinoma (NPC). The study included 175 patients with NPC and 279 age- and sex-matched control subjects. The ACE I/D polymorphism was identified by a polymerase chain reaction analysis. No association was found between the ACE I/D polymorphism and risk of NPC (ID vs. II: odds ratio [OR] = 0.77, 95% confidence interval [CI] 0.51-1.17; DD vs. II: OR = 0.98, 95%CI 0.56-1.72, respectively). This finding indicates that the ACE I/D polymorphism may not play a role in susceptibility to NPC. Further studies are warranted to confirm this finding, especially in ethnically disparate populations.

The association between ACE polymorphism and risk of colorectal cancer in a Chinese population

OBJECTIVES

Angiotensin I-converting enzyme (ACE) plays crucial roles not only in the regulation of circulatory homeostasis but also in the pathology of carcinomas. An insertion-deletion (I/D) polymorphism in intron 16 of ACE gene was identified to be functional. We aimed to investigate the association between ACE I/D polymorphism and risk of colorectal cancer (CRC).

DESIGN AND METHODS

Using genomic DNA from 241 CRC patients and 299 control subjects, we genotyped the ACE I/D polymorphism using a polymerase chain reaction analysis.

RESULTS

We found that patients carrying the D allele were associated with an increased risk of developing poorly differentiated cancer and metastasis compared with those carrying the I allele (OR=1.54, 95%CI, 1.04-2.28; OR=1.56, 95%CI, 1.08-2.26, respectively), although no significant association was observed between cases and controls in overall analysis.

CONCLUSIONS

These findings indicate that the ACE I/D polymorphism is likely to play a role in CRC progression.

Are 'endurance' alleles 'survival' alleles? Insights from the ACTN3 R577X polymorphism

Exercise phenotypes have played a key role for ensuring survival over human evolution. We speculated that some genetic variants that influence exercise phenotypes could be associated with exceptional survival (i.e. reaching ≥100years of age). Owing to its effects on muscle structure/function, a potential candidate is the Arg(R)577Ter(X) polymorphism (rs1815739) in ACTN3, the structural gene encoding the skeletal muscle protein α-actinin-3. We compared the ACTN3 R577X genotype/allele frequencies between the following groups of ethnically-matched (Spanish) individuals: centenarians (cases, n = 64; 57 female; age range: 100–108 years), young healthy controls (n = 283, 67 females, 216 males; 21±2 years), and humans who are at the two end-points of exercise capacity phenotypes, i.e. muscle endurance (50 male professional road cyclists) and muscle power (63 male jumpers/sprinters). Although there were no differences in genotype/allele frequencies between centenarians (RR:28.8%; RX:47.5%; XX:23.7%), and controls (RR:31.8%; RX:49.8%; XX:18.4%) or endurance athletes (RR:28.0%; RX:46%; XX:26.0%), we observed a significantly higher frequency of the X allele (P = 0.019) and XX genotype (P = 0.011) in centenarians compared with power athletes (RR:47.6%; RX:36.5%;XX:15.9%). Notably, the frequency of the null XX (α-actinin-3 deficient) genotype in centenarians was the highest ever reported in non-athletic Caucasian populations. In conclusion, despite there were no significant differences with the younger, control population, overall the ACTN3 genotype of centenarians resembles that of world-class elite endurance athletes and differs from that of elite power athletes. Our preliminary data would suggest a certain ‘survival’ advantage brought about by α-actinin-3 deficiency and the ‘endurance’/oxidative muscle phenotype that is commonly associated with this condition.

Is the ACE I/D polymorphism associated with extreme longevity? A study on a Spanish cohort

The 287 bp Ins(I)/Del(D) polymorphism [rs1799752] in intron 16 of the angiotensin-converting enzyme ( ACE) gene has been associated with extreme longevity (≥ 100 years) in some Caucasian and Asian cohorts, but this finding was not corroborated in other reports. We compared the allelic/genotypic frequency of the ACE I/D polymorphism among centenarians ( N = 64, 100—108 years, 89.1% female) and nonagenarians ( N = 47, 90—97 years, 76.6% female), and a control group of healthy young adults ( n = 434, age 20—40 years, 50% female). All participants were of the same Caucasian (Spanish) descent. The ACE I/D genotype met Hardy—Weinberg expectations in all the cohorts. Allelic and genotypic frequencies did not differ by sex in any of the study groups (all p > 0.2). There were no differences in allelic or genotypic frequencies between groups, for example the frequency of the D allele was 62.3% in controls vs. 65.3% in the elderly (64.8% in centenarians). In summary, the ACE I/D polymorphism is not significantly associated with extreme longevity in the Spanish population. Further research is, however, necessary using other approaches. It also remains to be determined if the interaction of ACE genotypes with some other genetic variants exerts a potential effect on longevity.