Blood Types and the Population. O positive is the most common blood type. Not all ethnic groups have the same mix of these blood types. Hispanic people, for example, have a relatively high number of Oâs, while Asian people have a relatively high number of Bâs.The mix of the different blood types in the U.S. population is:n addition to the A and B antigens, there is a third antigen called the Rh factor, which can be either present (+) or absent (â). In general, Rh negative blood is given to Rh-negative patients, and Rh positive blood or Rh negative blood may be given to Rh positive patients.
Medical Definition of LENTIGO. 1. : a small melanotic spot in the skin in which the formation of pigment is unrelated to exposure to sunlight and which is potentially malignant; especially: nevusâcompare freckle. 2. : freckle.
Lentigo maligna (also known as Lentiginous melanoma on sun-damaged skin) is a melanoma in situ that consists of malignant cells but does not show invasive growth.Lentigo maligna is not the same as lentigo maligna melanoma, and should be discussed separately.It typically progresses very slowly and can remain in a non-invasive form for years.t is normally found in the elderly (peak incidence in the 9th decade), on skin areas with high levels of sun exposure like the face and forearms. Some authors do not consider lentigo maligna to be a melanoma.