Eukaryotes Genomes - TRYPANOSOMA BRUCEI

Trypanosomes are unicellular, flagellated protozoan organisms, forming part of the order "Kinetoplastida". The order is characterised by the presence of one flagellum and a single mitochondrion containing the "kinetoplast", a specialised DNA containing organelle. Species of the parasite colonise vertebrates, invertebrates and plants. Some species are pathogenic, causing disease in humans and their domestic animals. Amongst these is T. brucei which causes African Trypanosomiasis (also known as Sleeping sickness) and the cattle wasting disease N'gana in sub-Saharan Africa.

African trypanosomiasis, is a severe disease, which is fatal if left untreated. It is closely related to the widespread cattle infection N'gana, which restricts cattle rearing in many prime areas of Africa. Sleeping sickness claims comparatively few lives annually, but the risk of major epidemics means that surveillance and ongoing control measures must be maintained.

Trypanosoma brucei, enter the blood-stream via the bite of bloodsucking male and female tse-tse flies that transfer the parasites from human to human. Cattle and other wild mammals act as reservoir hosts of the parasites. Tse-tse flies can acquire parasites by feeding on these animals, or on an infected person. Inside the human host, trypanosomes multiply and invade most tissues.

Infection leads to malaise, lassitude and irregular fevers. Early symptoms include fever and enlarged lymph glands and spleen. Early signs are followed by a range of symptoms including headache, anaemia, joint pains and swollen tissues; advanced symptoms include neurological and endocrine disorders.As the parasites invade the central nervous system, mental deterioration begins, leading to coma and death.

References:

Nucleic Acids Res. 31 (16):4856-4863 (2003)
http://www.who.int/tdr/diseases/tryp/lifecycle.htm
http://www.sanger.ac.uk/Projects/T_brucei/