The Navajo Indians are the largest federally recognized Native American Indian tribe in the United States. Their reservation is spread out through out the four corners of Arizona, New Mexico, Utah and Colorado. The Navajo use the name Dine because it refers to a term from the Navajo language that means people.
Males with Klinefelter's syndrome have two X chromosomes (47,XXY), in rare cases three (48,XXXY) or four (49,XXXXY) X-chromosomes. The X-chromosomes carry genes in terms of development of testicles, sex hormone production and physical sex development in general as well as to a certain extent also height growth.
What is the cause of the chromosome aberration in Klinefelter's syndrome? Certain chromosome aberrations appear more frequently in children of elderly mothers and, to a certain extent, also elderly fathers, but this is not the case of Klinefelter's syndrome, and today nothing definite is known about causes leading to an increase in the number of X-chromosomes as found in Klinefelter's syndrome.