There was "an initial rapid diversification" of K-M526, according to Karafet et al. (2014), which "likely occurred in Southeast Asia, with subsequent westward expansions of the ancestors of haplogroups R and Q". Phylogeny within K2b P P295/PF5866/S8 (also known as K2b2). P1 M45 (a.k.a.K2b2a) Q M242 (K2b2a1) R M207 (K2b2a2) R1 (M173) R1a (M420) R1b (M343) Internal structure of R1b Names such as R1b, R1b1 and so on are phylogenetic (i.e. "family tree") names which make clear their place within the branching of haplogroups, or the phylogenetic tree. An alternative way of naming the same haplogroups and subclades refers to their defining SNP mutations: for example, R-M343 is equivalent to R1b. Phylogenetic names change with new discoveries and SNP-based names are consequently reclassified within the phylogenetic tree. In some cases, an SNP is found to be unreliable as a defining mutation and an SNP-based name is removed completely. For example, before 2005, R1b was synonymous with R-P25, which was later reclassified as R1b1; in 2016, R-P25 was removed completely as a defining SNP, due to a significant rate of back-mutation. (Below is the basic outline of R1b according to the ISOGG Tree as it stood on January 30, 2017.) Geographical distribution R1b* (R-M343*) No confirmed cases of R1b* (R-M343*) – that is R1b (xR1b1, R1b2), also known as R-M343 (xL754, PH155) – have been reported in peer-reviewed literature. R-M343 (xM73, M269, V88) In early research, because R-M269, R-M73 and R-V88 are by far the most common forms of R1b, examples of R1b (xM73, xM269) were sometimes assumed to signify basal examples of "R1b*". However, while the paragroup R-M343 (xM73, M269, V88) is rare, it does not preclude membership of rare and/or subsequently-discovered, relatively basal subclades of R1b, such as R-L278* (R1b*), R-L389* (R1b1a*), R-P297* (R1b1a1*), R-V1636 (R1b1a2) or R-PH155 (R1b2). The population believed to have the highest proportion of R-M343 (xM73, M269, V88) are the Kurds of southeastern Kazakhstan with 13%. However, more recently, a large study of Y-chromosome variation in Iran, revealed R-M343 (xV88, M73, M269) as high as 4.3% among Iranian sub-populations. R1b subclades have also been found in Han Chinese from Shandong, Heilongjiang and Gansu provinces. It remains a possibility that some, or even most of these cases, may be R-L278* (R1b*), R-L389* (R1b1a*), R-P297* (R1b1a1*), R-V1636 (R1b1a2), R-PH155 (R1b2), R1b* (R-M343*), R1a* (R-M420*), an otherwise undocumented branch of R1 (R-M173), and/or back-mutations of a marker, from