against that of APOE in view of our recent findings for APOE 1 4 in our centenarians (9). We did not find statistically significant differences in rates between alleles and centenarians among the stratified for (Table 2). However, we did find a statistically decreasing gradient from Northern to Southern of Europe in ACE1*I allele frequency both in and controls (z ¼ 3: 31; p ¼ 0: 001; z ¼ 3: 62;

Table 2

Angiotensin I converting enzyme 1 (ACE1) genotype and allele distribution according to apolipoprotein E (APOE) alleles presence in Italian centenarians and middle-aged subjects

Genotypes n frequency (95% CI) Alleles n frequency (95% CI) ACE1*I/*I ACE1*I/*D ACE1*D/*D ACE1*I ACE1*D Italian centenarians ðn ¼ 82Þ APOE 12 4 9 10 17 29 0.17 (0.37–0.07) 0.39 (0.59–0.22) 0.44 (0.63–0.26) 0.37 (0.51–0.25) 0.63 (0.76–0.49) APOE 13 15 59 64 89 187 0.11 (0.17–0.07) 0.43 (0.51–0.35) 0.46 (0.55–0.38) 0.32 (0.38–0.27) 0.67 (0.73–0.62) APOE 14 1 0 2 2 4 0.33 (0.79–0.06) 0.0 (0.56–0.0) 0.67 (0.94–0.21) 0.33 (0.70–0.10) 0.67 (0.90–0.30) Italian controls ðn ¼ 252Þ APOE 12 4 26 22 34 70 0.08 (0.18–0.03) 0.50 (0.63–0.37) 0.42 (0.56–0.30) 0.33 (0.42–0.24) 0.67 (0.76–0.58) APOE 13 62 196 164 320 524 0.15 (0.18–0.12) 0.46 (0.51–0.42) 0.39 (0.44–0.34) 0.38 (0.41–0.35) 0.62 (0.65–0.59) APOE 14 2 14 14 18 32 0.06 (0.21–0.02) 0.47 (0.64–0.30) 0.47 (0.64–0.30) 0.30 (0.43–0.20) 0.70 (0.80–0.58)

n; number of individuals genotyped; CI, confidence interval.

F. Panza et al. / Experimental Gerontology 38 (2003) 1015–1020

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compared to elderly women and controls. In this older population, the ACE1*I/*I genotype was depleted only in elderly males suggesting an influence of sex on the penetrance of ACE1 locus (Galinsky et al., 1997). A subsequent study on Danish centenarians did not confirm the impact of ACE1 gene polymorphism on longevity (Bladbjerg et al., 1999). Finally, retyping the 1994 centenarian cohort of Shachter for the ACE1 polymorph- ism revealed a 5% difference with the original data with the ACE1 allele frequencies. These differences were homo- geneously distributed between gender in both populations of centenarians and controls (Blanche` et al., 2001). The French centenarians and controls of the Shachter cohort were not matched for geographical origin, 20% of the centenarians were born outside of France or had unknown birthplaces, suggesting heterogeneity in the geographical distribution of the ACE1 polymorphism.

in ACE1*D allele frequency was also observed (z ¼ 3: 31; p ¼ 0: 001; z ¼ 3: 62; p ¼ 0: 001; respectively) (Table 1). This was also reflected in the ACE1*D/*D genotype data whereby a similar statistically significant increasing geo- graphical gradient from North to South was found in centenarians and the younger controls (cases: z ¼ 3: 29; p ¼ 0: 001; controls: z ¼ 3: 26; p ¼ 0: 001). An inverse statisti- cally significant gradient was found for the ACE1*I/*I genotype, but only in control subjects (z ¼ 2: 65; p , 0: 01) while in centenarians there was a borderline p-value (z ¼ 1: 93 asymptotic-p ¼ 0: 053; exact-p ¼ 0: 063). We did not find any statistically significant decreasing gradient from Northern to Southern regions for the ACE1*I/*D genotype neither in centenarians nor in controls.

4. Discussion

allele frequency decreases according to a geographical gradient from Northern to Southern Europe in centenar- ians. Conversely, the ACE1*D allele frequency appears to increase in the opposite direction (from South to North). These data confirm previously published results on regional differences of the ACE1*D allele frequency within France (3%) and between Northern Ireland and Southern France (7%) (Cambien et al., 1992) which we also observed in our investigation of the role of geographic gradients on ACE1 involvement in AD (Panza et al., 2003). In the present study there is a statistically significant difference of 15% between the ACE1*D allele frequency between Danish and Southern Italian centenarians and of 9% between France and Italy. In these three geographical sites ACE1 allele frequencies were homogeneously distributed between gender in both populations of centenarians and controls, confirming the recent data of another Italian study with a focus on ACE1 polymorphism and insulin resistance (Paolisso et al.,

The present study did not provide evidence to support the suggested role of the ACE1 polymorphism in increased human longevity due to an increase of ACE1*D allele in centenarians compared to control subjects aged between 20 and 70 years (Schachter et al., 1994). However, a post hoc power calculation revealed that the present study has only sufficient statistical power to exclude an allele frequency difference of about 12% and the power is even less considering the fact that gene–gene interaction were investigated.