Robertsonian translocation
（重定向自Robertsonian fusion）
Robertsonian translocation (ROB) is a rare form of chromosomal rearrangement that, in humans, occurs in the five acrocentric chromosome pairs, namely 13, 14, 15, 21 and 22. Other translocations occur but do not lead to a viable fetus. They are named after the American biologist William Rees Brebner Robertson Ph.D. (1881–1941), who first described a Robertsonian translocation in grasshoppers in 1916. They are also called whole-arm translocations or centric-fusion translocations. They are a type of chromosomal translocation.