The x should be the number of transcripts that produce functional protein sequences. One transcript should correspond to one protein sequence, and vice versa. Every UniGene cluster should correspond to one gene and every TC in TGI should correspond to one protein sequence, and vice versa. ASPicDB uses a better algorithm because it makes all transcripts correspond with genes and proteins very well. The value of x is very important because the effective information is roughly proportional to x. The diversity of proteins before posttranslational modifications can reflect the complexity of organisms.