Detection of 53 FBN1 mutations (41 novel and 12 recurrent) and genotype-phenotype correlations in 113 unrelated probands referred with Marfan syndrome, or a related fibrillinopathy.

Mutations in the gene encoding fibrillin 1 (FBN1) cause Marfan syndrome (MFS), and related connective tissue disorders. The disease spectrum is wide and while many genotype-phenotype correlations have been reported, few have been consistent. In this study FBN1 was analyzed in 113 patients with MFS or Marfan-like features. Fifty-three mutations were identified in 52 individuals, 41 of which were novel. The mutations comprised 26 missense, 11 splice site, 7 frameshift, 6 nonsense, 1 in-frame deletion, and 2 whole exon deletions. In common with previous studies, genotype-phenotype analysis showed that a FBN1 mutation was more likely to be identified in patients fulfilling Ghent criteria (P = 0.005) and in those who had ectopia lentis (EL) (P < 0.0001). Other previously reported genotype-phenotype correlations were also considered and a new inverse association between a mutation in exons 59-65, and EL emerged (P = 0.002).

Do ponds cause arsenic-pollution of groundwater in the Bengal basin? An answer from West Bengal.

We report time-series data collected over two years for delta18O, delta2H, and Ca, Mg, K, and Cl, concentrations for 10 ponds in, and upflow of, an As-polluted region of southern West Bengal. We compare the compositions of As-polluted groundwaters from wells with the compositions of waters in ponds upflow, and within the range of influence, of the wells. Conservative tracers (delta18O, delta2H, K), and other tracers (Ca, Mg) that are likely conservative in the waters, showthat pondwater and groundwater are distinct and do not overlap in composition. These data show that water from ponds cannot be identified in As-polluted groundwater, so putative DOC in pondwater cannot be mixing into the As-polluted groundwater we have sampled. Separate estimates of the degree of recharge from ponds to groundwater, using calculations based on temporal variations in salt content and isotopic composition in ponds, and salt-balance, show that insignificant amounts of As-polluted groundwater are derived via pond recharge. It follows that pondwater in the study area does not contribute significant mass to arsenic-polluted groundwater and so does not provide organic matterto aquifers in amounts sufficientto drive reduction of iron oxyhydroxides and hence arsenic pollution.

Regional geochemical mapping.

One of the prime requirements for effective study of environmental geochemistry in relation to health is the production of multi-element atlases showing the distribution of the elements on the regional scale. The choice of method for compiling such atlases can vary according to a number of geological, environmental and other factors. The overriding consideration, however, is to assist (in conjunction with other relevant sources of information) in defining, quickly and cheaply, potential problem areas wherein to concentrate more detailed studies to ensure maximum return from the funds and scientific manpower available. Numerous sampling and analytical techniques have been employed. Each technique and approach has its own scope, limitation and problems of interpretation. Whatever method is chosen, the use of computer-based statistical data reduction, analysis and map compilation is mandatory. Although it was apparent more than 20 years ago that geochemical atlases would eventually become a national cartographic requirement, regional geochemical mapping is still in the experimental stage. This trend is now evident in activity in a number of countries. The methods being employed, however, are so diverse that there is an urgent need for international collaboration aimed at securing data that are as mutually compatible as possible, having regard to the conditions, needs and resources of the individual countries involved.