Identification and phylogenetic analysis of neuroligin family members. A: There are 38 autosomes and two sex chromosomes (W,Z) in the chicken. The identity of the chromosomes carrying possible NLGN homologs were identified with the Ensembl gene browser and are indicated by horizontal arrowheads. B: Percent identity between the coding regions of human and chicken NLGN genes calculated using a ClustalW alignment shows the degree of homology between the chicken and human orthologs. C: A rooted tree layout cladogram displaying the evolutionary relationships between vertebrate and non-vertebrate animals includes Anolis carolinensis (Lizard), Acyrthosiphon pisum (pea aphid), Aedes aegypti (yellow fever mosquito), Bos taurus (bovine), Danio rerio (zebrafish), Equus caballus (horse), Gallus gallus (chicken), Homo sapiens (human), Mus musculus (mouse), Pan troglodytes (chimpanzee), and Rattus norvegicus (rat). Accession numbers used for alignments and tree building are listed within the dendrogram.