Letters in lower case have no entries. Acronyms not appearing in the glossary, may be included in the List of Acronyms at the end of the glossary. Alleles Variant forms of the same gene.
Different alleles produce variations in inherited characteristics such as eye color or blood type.
A protein excreted by the fetus into the amniotic fluid and from there into the mother's bloodstream through the placenta. Amino acid Any of a class of 20 molecules that are combined to form proteins in living things. The sequence of amino acids in a protein and hence protein function are determined by the genetic code. The linear order of the amino acids in a protein or peptide. Amniocentesis Prenatal diagnosis method using cells in the amniotic fluid to determine the number and kind of chromosomes of the fetus and, when indicated, perform biochemical studies.