ALBERT

Notes: Abstract AnArthrobacter strain isolated from soil and selected for poor ability to utilize hexadecane as sole C-source was grown in a hexadecane (or pentadecane) — salts medium supplemented with yeast extract or corn steep liquor as the source of carbon for growth. It accumulated mono-hexadecanones (or pentadecanones). The percentages to which the individual ketones were accumulated depended on the distance of the carbonyl group from the terminal end of the substrate hydrocarbon; the greater the distance, the lower the percentage. The percentages did not depend on the composition of the medium. No other hydrocarbon oxidation products were observed. These results are discussed in relation to other reports of microbial conversions of alkanes to ketones.

Notes: Summary The authors describe two families from the upper Valais with a common ancestor who had lived in the beginning of the 19th century. After a consanguineous marriage in both families, four cases of myoclonic epilepsy occurred among the children (V/2 and 4; V/12 and 15). In the first sibship there were in addition five cases of pigmentary retinopathy associated in our propositus case to myoclonic epilepsy. In the second sibship, myoclonic epilepsy was not accompanied by any other disturbances. Parental consanguinity and familial occurrence of the disease clearly indicate a recessive transmission of myoclonic epilepsy and of pigmentary retinopathy. Myoclonias and the first epileptic fits occurred around the age of puberty and were soon followed by progressive dementia. Pigmentary retinopathy, studied particularly in the propositus, was rather atypical and consisted of pigment deposits in form of osteoblasts in the periphery and of some disseminated whitish foci reminiscent of retinitis punctata albescens. The electroretinogram was abolished in all cases. The pathological examination of the propositus, a woman who died at the age of 37, did not reveal the classical Lafora corpuscles. However, small, apparently free corpuscles were found in the neuropil, showing a rosette structure by PAS reaction. Furthermore, PAS-positive deposits (mucopolysaccharides) were found in several organs (myocard, small vessels of the spleen, Kupffer's and liver cells, skeletal muscle, kidneys). Neutral mucopolysaccharides were also present in the glia of the posterior pituitary lobe. There were no signs permitting to consider the association of myoclonic epilepsy and pigmentary retinopathy found in our propositus as a myoclonic form of familial amaurotic idiocy. It appears that this case should rather be connected with the already long list of retinal abiotrophies accompanying neurological disturbances. A fortuitous association of the two heredodegenerations, however, cannot be excluded. Whereas the distribution of the mucopolysaccharides in the nervous system and the other organs corresponds to the descriptions of the literature, the absence of Lafora corpuscles induces the authors to consider their propositus case as a new type of myoclonic epilepsy for which they propose the name “acorpuscular form”.

Notes: Conclusions and Summary The authors begin with a historical review of the first genetic investigations concerning familial amyloidotic polyneuropathy in the North of Portugal by C. Andrade. Then they review the studies made by other authors about this curious hereditary disease. A dominant mode of transmission was found in all investigations and the area of Povoa de Varzim could be confirmed as the focus where the mutation took place for the first time. Later on the affection spread throughout the northern part of Portugal before finally migrating also to the American continent. The early inquiries of Andrade in 1951–52 were concerned with a still fairly limited number of cases (74 cases). A systematic genetic and statistical study became, however, necessary for the whole material collected over almost 30 years by C. Andrade et al. The individuals examined now amount to 623, 249 of whom are affected (153 males and 96 females, distributed over 148 sibships). After applying various methods of correction (maximum-likelihood-method and Weinberg's method) and while making a distinction between simple selection (k=0) and complete selection (k=1), the authors come to the following evaluations: for K=0, the average of individuals affected (corrected) per sibship is of 21.26±1.88% (method of maximum likelihood scores); for k=1, this value is of 30.84±2.26%. When considering separately within the sibships the male and female patients, the following figures are obtained: for k=0, respectively 13.06±1.33% for males and 8.20±0,98% for females; for k=1, 18,95±1.68% for males and 11.89±1.29% for females. The percentages obtained with Weinberg's method are more or less the same (21.26±1.75% and 31.39±2.50% for k=0 and k=1, respectively). Since the material was collected during a systematic survey of all families affected, the figures computed for k=1 (complete selection) must be considered correct (30.8% by the maximum-likelihood-method and 31.4% by Weinberg's method). In respect of the sex ratio in the families studied, a predilection for the male sex was revealed when all families with at least one member affected are taken into account. However, when considering the families with at least two members affected, the sex ratio corresponds to 1:1. As to morbidity risk, our values are clearly below those of Becker (1964): whereas the figures found by Becker range between 0.32 and 0.50, ours lie between 0.26 and 0.31. The discrepancy must be attributed to the fact that our material which was numerically more important than Becker's provided for a more equitable evaluation of the sex ratio and excluded the possibility of a sex controlled gene. According to our investigations, there is therefore no difference between the sexes as to the degree of penetrance of the affection. The discordance between the sexes is practically restricted to the age of manifestation of the disease, 33 years on an average for males and 44 years for females. The assumption must consequently be made that this one difference is sufficient to guarantee transmission of amyloidotic polyneuropathy through the generations, in spite of counterselection that operates to the detriment of the responsible gene.