1 Down syndrome, usually is caused by an extra copy of chromosome 21 (trisomy 21). Characteristics include decreased muscle tone, asymmetrical skull, slanting eyes and mild to moderate mental retardation.  Edward's syndrome, which is the second most common trisomy after Down syndrome. It is a trisomy of chromosome 18.
Guanxi describes the basic dynamic in personalized networks of influence, and is a central idea in Chinese society.
Yunnan is a province of the People's Republic of China, located in the far southwest of the country. It spans approximately 394,000 square kilometres (152,000 sq mi) and has a population of 45.7 million in 2009. The capital of the province is Kunming, formerly also known as Yunnan.