||Some additional topics have been addressed. For instance,
basic mechanisms involved in the folding of integral membrane proteins
were studied using bacteriorhodopsin as a model.
The structure-function-studies on factor H, a human serum protein with complement regulatory activity, were continued. Similar and comparative analyses have been started with a factor-H analogue of a primitive vertebrate. The comparisons are expected to yield interesting phylogenetic insights.
A new member has joined the growing family of human proteins with structural similarity to factor H. It was recognized by cDNA screening. With respect to its function - and to the func-
tions of the other three family members known to date - a first indication may be derived from the fact that the new member was in parallel identified as an apolipoprotein.
The mechanisms of action of certain transcription factors are studied in increasing detail with the interleukin-2 gene of T lymphocytes. In the context of these studies, a difference has been observed between the subtypes of Th1 and Th2 helper cells. This finding may mark an additional step in the analysis of the regulation of the T-helper dichotomy, which is con-
sidered to be of great importance for the defence against infectious agents.
In the past year, the first successful genome-wide linkage analysis was performed in humans for a parasitic disease; a French group of scientists localized a susceptibility-resistance locus for schistosomiasis to chromosome 5. The result was immediately confirmed and extended in our laboratories. And the task continues to collect in the endemic area of tropical diseases samples of family members which are reliably characterized as phenotypes. In this respect, the opening of the new co-operative African research unit of the institute is awaited eagerly.
So far, the Department of Molecular Genetics continues to include work on the mapping of classical monogenic diseases. Three neurologic disorders are currently being analysed, a locus for congenital deafness has been delineated in more detail.
A project on the genetic basis of bovine trypanotolerance has been continued in collabora-
tion with the International Livestock Research Institute, Nairobi. There, three candidate re-gions have been identified in a mouse model. We have confirmed the major histocompatibility complex as one of them in cattle und have begun with its physical mapping. Recent experiments on the trypanolytic activity of human serum have added haptoglobin and related proteins as candidates; accordingly, the corresponding gene of cattle has been included in the studies.
|For additional information please also see Investigators’ Reports.|
Prof. Dr. Rolf D. Horstmann