Figure 2.

Impact of Sexual Reproduction and Ploidy on the Transmission of KO Alleles

(A) Schematic illustrating ploidy changes during sexual and mosquito stages (adapted with permission from Lee et al., 2014).

(B) Illustration of inheritance where KO of gene a leads to a strong reduction in fertility in both sexes. Reduced transmission (red) of a^- from less fertile gametes is not rescued (dotted arrows) by cross-fertilization with a⁺ parasites (solid arrows), leading to much reduced inheritance of the a^- allele. The line graph displays screen data from known fertility genes showing strong reductions of the corresponding barcode (strongly negative log₂FC) among midgut (MG) oocysts.

(C) As in (B), but assuming a sex specific fertility phenotype for gene b, allowing the b^- alleles to be transmitted effectively by the fertile sex. The line graph shows real data for genes with known functions, illustrating how the expected log₂FC or −1 is barely noticeable.

(D) Similar illustration for a hypothetical gene c with known function in ookinete or oocyst development. Inheritance of c^- allele may be almost unhindered due to heterozygous rescue. Real data are plotted for genes whose homozygous disruption is known to block ookinete development or infectivity. Error bars in the line graphs shown in (B), (C), and (D) show standard deviations from three replicate transmissions of the same mutant pool.