Chromosomal Distribution of A. gambiae Orthologs ofD. melanogaster Genes
| Drosophilaregions, no. of observed and expected genes, and P values of binomial test | A. gambiae polytene chromosome arms | ||||
| X | 2R | 2L | 3R | 3L | |
| X-tip, divisions 1–3 (19 genes) | |||||
| Observed genes | 3 | 5 | 2 | 4 | 5 |
| Expected genes | 2.27 | 5.58 | 4.13 | 3.82 | 3.20 |
| P value of binomial test | 0.719 | 0.81 | 0.283 | 1 | 0.35 |
| Adh region of2L (31 genes) | |||||
| Observed genes | 0 | 4 | 1 | 24 | 2 |
| Expected genes | 3.71 | 9.10 | 6.74 | 6.23 | 5.22 |
| P value of binomial test | (0.028) | (0.048) | (0.0079) | 9.939 e−12 | 0.15 |
[i] The binomial test was applied as follows. For each of the twoD.melanogaster regions analyzed, the number of putative orthologs observed in each A. gambiae polytene chromosome arm was listed. The corresponding expected number of orthologs was calculated according to the number of lettered subdivisions perAnopheles chromosomal arm (see Results), and the P value was determined by the binomial test. Statistically significant results are shown in bold, within or without parantheses depending on whether genes are underrepresented or overrepresented in that arm, respectively. Note that Adh region orthologs are significantly overrepresented in the mosquito 3R arm and underrepresented in X, 2R,and 2L.