1082 Since 1966 we have performed 34 autotransplantations and 3 splenorenal anastomoses by retroperitoneal approach. We have no morbidity or mortality and the average of successful results on arterial hypertension is 81%. Cátedra de Urologia, Facultad de Medicina, Universidad de Barcelona,
J. M. GIL-VERNE
SIR,-Dr Waldron and Dr Waterhouse (April 10, p. 805) .
decline in consumption in the U.S. seems to have petered out in 1969, whereas in the U.K. it has only recently started. This may be partly because the "fairness doctrine" in the U.S., under which all television stations showing cigarette commercials were required to show anti-smoking films, ended with the ban on television cigarette advertising, and partly because Federal tax on cigarettes in the U.S. has not increased since 1954, whereas the past three years in the U.K. have each seen significant increases in tobacco duty. ASH (Action on Smoking and 27-35 Mortimer Street, London W1A 4QW
criticise the figure of 45-80 times the rate in the general population for the incidence of scrotal cancer among toolsetters and machine operators in Dalton’s booklet.’ They state that, "on
possible basis, the incidence ... exceeds that of the total male population by about 17 times". Unlike Mr Dalton, however, they have not used the national figures for compariIn their report to the Institute of Petroleum2 the national incidence is given as 1 or 2 cases per million. Using their own figures again (cited in their letter), the rate of at most 100 cases per million in tool setters and machine operators is between 50 and 100 times as great. The figures they did use for comparison were those for the West Midlands region, presumably higher than the rest of the country because of occupational exposure. Even if one assumes that different standards of reporting to cancer registries necessitate such a comparison, their technique is statistically invalid. Because nearly half (44.7%) of the cases of scrotal cancer occur in the relatively small occupational group of toolsetters and machine operators, the rate for all males has been grossly inflated. One must therefore compare the rate for the occupational group not with that for all males but with that for other males. The rate in toolsetters and machine operators is then found to be about 30 times that of other males. Indeed this figure may itself be slightly low, since the 7% of cases of scrotal cancer whose occupations were unknown have all been taken as "other" males. T.U.C. Centenary Institute of Occupational Health, London School of Hygiene and Tropical Medicine, London WC1E 7HT
ASPARTYLGLYCOSAMINURIA IN NORTHERN
SIR,-Aspartylglycosaminuria is an autosomal recessive dismarked by progressive dementia which is associated with a deficiency of the glycoprotein-degrading enzyme aspartylglucosylaminase (E.C.126.96.36.199).’ Finland seems to have the highest incidence of this disease-’ (1 case/26 000 newborn). Thus, 71 cases were known in Finland up to 1974,3and elsewhere the disease is very rare. 2 cases have been reported in England’ (from the same family) and 1 in the U.S.A.4 These 3 latter
persons of Finnish descent. We wish to report 6 new cases of aspartylglycosaminuria in northern Norway in four families of Finnish ancestry. Using two-dimensional thin-layer chromatography/ we are now screening aminoacids in urine samples from mentally retarded patients, and among 200 such patients we have detected 6 with aspartylglycosaminuria. Although the aminoacid pattern in blood is normal, this disease may be detected
cases were not
CONCENTRATION OF A.A.D.G. IN URINE FROM
SIR,-Dr Bradshaw writes (April 24, p. 912) that "the Americans have certainly been more successful than ourselves in giving up cigarettes." This used to be so, but is no longer true. In recent years cigarette consumption has been declining in the U.K., but increasing in the United States. The figures for sale of manufactured cigarettes (those for the U.S.A. include consumption by Forces abroad) are, in millions:
Sources: Economic Research Service, U.S. Department of Agriculture, and Tobacco Research Council, London.
Excluding rogue years, such as those following reports of the Royal College of Physicians (1962 and 1971) in the U.K. and the first Surgeon General’s report (1964) in the U.S., the a Worker’s Guide to the Health Hazards and How to Fight Them. British Society for Social Responsibility in Science, London, 1976. 2. Brown, A. J., Waldron, H. A., Waterhouse, J. A. H. Report on a Study of Occupational Skin Cancer. University of Birmingham, 1975.
Dalton, A. Oil:
estimated semiquantitatively on bidimentional thin-layer chromatospraying with ninhydrin/2, 4, 6,-collidine, with the commercial stanat the same time as the samples. Spots on chromatograms were
by examining 2-acetamido-l-(p-L-aspartamido)-l, 2-dideoxy-&bgr;D-glucose (A.A.D.G.) levels in urine. The detection of A.A.D.G. in urine is straightforward in our cellulose thin-layer chromatographic system (details to be published elsewhere). However, A.A.D.G. is easily overlooked when aminoacid analysis is undertaken by the method of Stein and Moorebor by one-way highvoltage electrophoresis. In the first method the problems are A.A.D.G. decomposition and overlapping of the A.A.D.G. and urea peaks; in the second, confusion may arise because of overlapping with proline, a substance which after spraying with ninhydrin/2,4,6,-collidine gives a colour similar to that given by A.A.D.G. The detection of A.A.D.G. was confirmed by (1) isolation of the compound and identification of aspartic acid and glucosamine as products of its hydrolysis; (2) examination of the chro1. 2. 3. 4. 5. 6.
Pollitt, R. J., Jenner, F. A., Merskey, H. Lancet, 1968, ii, 253. Autio, S. J. ment. Def. Res. Monogr. SeriesI, 1972. Aula, P., Autio, S., Raivo, K., Näntö, V. Humangenetik, 1974, 25, 307. Isenberg, J N., Sharp, H. L. J. Pediat. 1975, 86, 713. Saiter, A. Adv. clin. Chem. 1971,14, 146. Palo, J., Pollitt, R. J., Pretty, K. M., Savolainen, H. Clinica, chim. Acta. 1973, 47, 69.