McCune-Albright syndrome (MAS) is a rare, genetic, non-inherited condition that causes bone tumors, bone deformity and fractures. The manifestations include polyostotic fibrous dysplasia, café au lait spots, and precocious puberty. Mutation of the GS gene in chromosome 20q13 occurs early in development, and results in a mosaic of abnormal and mutated cells. The manifestations of MAS in each individual depend upon the extent and distribution of abnormal cells. The impact factor of journal provides quantitative assessment tool for grading, evaluating, sorting and comparing journals of similar kind. It reflects the average number of citations to recent articles published in science and social science journals in a particular year or period, and is frequently used as a proxy for the relative importance of a journal within its field. It is first devised by Eugene Garfield, the founder of the Institute for Scientific Information.The impact factor of a journal is evaluated by dividing the number of current year citations to the source items published in that journal during the previous two years.