Similar results have been found in other studies [17] [18]. Based on these reports we have defined hard-to-heal ulcers in this study as venous leg ulcers with an initial area of 10cm2 or greater and a duration of six months or more.
A gene is a segment of DNA containing the code used to synthesize a protein. A chromosome contains hundreds to thousands of genes. Every human cell contains 23 pairs of chromosomes, for a total of 46 chromosomes. A trait is any gene-determined characteristic and is often determined by more than one gene. Some traits are caused by abnormal genes that are inherited or that are the result of a new mutation.
How many chromosomes do people have? In humans, each cell normally contains 23 pairs of chromosomes, for a total of 46. Twenty-two of these pairs, called autosomes, look the same in both males and females. The 23rd pair, the sex chromosomes, differ between males and females. Females have two copies of the X chromosome, while males have one X and one Y chromosome. The 22 autosomes are numbered by size. The other two chromosomes, X and Y, are the sex chromosomes. This picture of the human chromosomes lined up in pairs is called a karyotype.