Abstract
Between 1976 and 2003, we diagnosed 144 patients with familial amyloid polyneuropathy (FAP) in the Balearic Islands (Spain). Analysis of genetic epidemiological data from 102 confirmed patients showed 62% were men. Parental transmission was paternal in 38, maternal in 25, and unknown in 39. No family history of FAP was found in 32 patients. TTRVal30Met associated with haplotype I was present in the individuals studied. Mean age-at-onset was 45.7 years which lies between that of Sweden and those of Portugal, Japan and Brazil. Duration of FAP was of 9.7 years. Age-at-onset, age-at-death, duration and fertility were similar between sexes. Twenty-nine intergeneration familial pairs of patients were ascertained. Raw anticipation was positive in twenty-four pairs, zero in one, and negative in four. Differences greater than 9 years between age-at-onset of the first and second member were considered relevant; positive relevant anticipation was found in 76% of the whole pairs. The frequency of positive anticipation of parent-child pairs was not significantly different than those described in the Swedish and Portuguese series. Significant positive correlation in age-at-onset was confirmed in twenty-seven types of pairs supporting the hypothesis that a genetic factor may modulate age-at-onset. The Balearic focus of FAP is expanding and constitutes a public health problem.
FAP, familial amyloid polyneuropathy; TTR, transthyretin
FAP, familial amyloid polyneuropathy; TTR, transthyretin