Widespread Divergence of the CEACAM/PSG Genes in Vertebrates and Humans Suggests Sensitivity to Selection

Chang, Chia Lin; Semyonov, Jenia; Cheng, Po Jen; Huang, Shang Yu; Park, Jae Il; Tsai, Huai-Jen; Lin, Cheng-Yung; Grützner, Frank; Soong, Yung Kuei; Cai, James J.; Hsu, Sheau Yu Teddy

Contrastingly, zebrafish and stickleback each contained at least ten CEACAM homologs ( Fig. 1c ; Table S3 in File S1). Most zebrafish homologs were found on two WGD-derived syntenic chromosome fragments that also contained co-orthologous ATP1A3 genes (ATP1A3a and 3b) as well as orthologs of ETHE1, ZNF574, PAFAH1B3, CNFN, LIPE, APOE, and TOMM40. In sticklebacks, at least five homologs on genome group XX (GacCEACAMI-V) were located close to marker genes CNFN, PAFAH1B3, XRCC1, and ETHE1. On the other hand, the medaka fish (O. latipes) contained only one CEACAM homolog on chromosome 16, which was surrounded by homologs of ATP1A3, PAFAH1B3, CNFN, LIPE, and TMEM145. Likewise, the West Indian Ocean coelacanth (L. chalumnae) contained at least one CEACAM homolog (DNA scaffold JH127065.1). Interestingly, a CEACAM homolog was also identified in a cartilaginous fish, little skate (L. erinacea; Class Chondrichthyes; FF598979.1, EE990618.1, and FF601895.1 in the EST database).