Chromosomal maps of human and amphioxus FGF1/2 and FGF4/5/6 genes loci. Synteny is well conserved among vertebrates and amphioxus for FGF1/2 (orange—upper part) and for FGF4/6 (red), which are also syntenic with FGFs 19/21/23 (brown) and with FGF3 (yellow—lower part). The synteny of FGF5 with BMP3, PAQR3, and ANXA3 suggests that this gene belongs to the FGF4/5/6 subfamily, but was probably secondarily translocated with his neighboring genes (BMP3, PAQR3, etc.) close to ANXA3.
