Table 1.

P-values for the stop codon frequencies in four Gene Expression Barcode categories

Gene Expression Barcode category	p(x ≤ n.TAA)	p(x ≥ n.TAA)	p(x ≤ n.TAG)	p(x ≥ n.TAG)	p(x ≤ n.TGA)	p(x ≥ n.TGA)
Pr = 0	0.2063	0.8067	0.8275	0.1844	0.4802	0.5354
0 < Pr ≤ 0.5	0.2502	0.7571	0.1865	0.8199	0.9150	0.0881
0.5 < Pr < 1	0.9994	7.03E-04	0.5168	0.5061	1.55E-03	0.9987
Pr = 1	1.0000	1.07E-08	5.00E-02	0.9684	4.61E-05	1.0000

Genes were clustered into four categories by proportion of cell types in which a gene was estimated as expressed (Pr). P-values were computed on the basis of Poisson binomial cumulative distribution. The probability p of codon occurrence in each gene was set equal to the codon fraction expected at the GC-content of its CDS