proctoscopy, and aspirates of abscesses or other tissue specimen. A blood test is also available, but it is recommended only when a healthcare provider believes the infection may have spread beyond the intestine to some other organ of the body, such as the liver. However, this blood test may not be helpful in diagnosing current illness, because the test can be positive if the patient has had amebiasis in the past, even if they are not infected at the time of the test. Stool antigen detection and PCR are available for diagnosis, and are more sensitive and specific than microscopy. Treatment There are a number of effective medications. Several antibiotics are available to treat Entamoeba histolytica. The infected individual will be treated with only one antibiotic if the E. histolytica infection has not made the person sick, and will most likely be prescribed two antibiotics if the person has been feeling sick. Otherwise, below are other options for treatments. Intestinal infection: Usually nitroimidazole derivatives (such as metronidazole) are used, because they are highly effective against the trophozoite form of the amoeba. Since they have little effect on amoeba cysts, usually this treatment is followed by an agent (such as paromomycin or diloxanide furoate) that acts on the organism in the lumen. Liver abscess: In addition to targeting organisms in solid tissue, primarily with drugs like metronidazole and chloroquine, treatment of liver abscess must include agents that act in the lumen of the intestine (as in the preceding paragraph) to avoid re-invasion. Surgical drainage is usually not necessary, except when rupture is imminent. People without symptoms: For people without symptoms (otherwise known as asymptomatic carriers), non-endemic areas should be treated by paromomycin; other treatments include diloxanide furoate, and iodoquinol. There have been problems with the use of iodoquinol and iodochlorhydroxyquin, so their use is not recommended. Diloxanide furoate can also be used by mildly symptomatic persons who are just passing cysts. Meiosis In sexually reproducing eukaryotes, homologous recombination (HR) ordinarily occurs during meiosis. The meiosis-specific recombinase, Dmc1, is required for efficient meiotic HR, and Dmc1 is expressed in E. histolytica. The purified Dmc1 from E. histolytica forms presynaptic filaments and catalyzes ATP-dependent homologous DNA pairing and DNA strand exchange over at least several thousand base pairs. The DNA pairing and strand exchange reactions are enhanced by the eukaryotic meiosis-specific recombination accessory factor (heterodimer) Hop2-Mnd1. These processes are central to meiotic recombination,