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.
Lentigines (pleural of lentigo) are flat brown lesions which do not darken following sun exposure (thus differentiating them from ephelides or true freckles). One study of Caucasian women found that lentigines were signs of photo-damage whereas there was a genetic component in true freckles. Lentigines profusa-in this condition, there are widespread lentigines over the arms, legs and genitalia. 2  There are no trigger factors or associated abnormalities (thus differentiating them from a number of lentigo-associated syndromes, see below).