Online handles and genetics

The connection between Homestuck and DNA is the sixteen online handles, each one in use by the four Homestuck Kids and the twelve Trolls, yet it is worth noting that even as of the beginning of the adventure, this is no longer the case, since John changed his handle to EctoBiologist so as to avoid the Trolls.

GCAT is a common presentation of the pairings of bases in the double helix structure of DNA, but in Homestuck is also a summary of the combinations of online handle abbreviations. G-C-A-T can be expanded into sixteen combinations of two-letter forms:

GG, GC, GA, GT, CG, CC, CA, CT, AG, AC, AA, AT, TG, TC, TA, TT

Each of these two-letter pair is the abbreviation used for an online handle of one of the trolls or kids (except for John):

The four human heroes comprise 1/4 of the listed pairs. It might be worth nothing that their combinations do not include the letters A or C. It's worth noting that of the four kids, John and Dave used to (before John changed his chumhandle to ectoBiologist) have GT and TG, while Rose and Jade have TT and GG, corresponding to male XY chromosomes and female XX chromosomes. The two remaining same-letter combinations (AA and CC) do belong to female trolls, but the remaining female trolls are GA, GC, AC, and AG. The number of female trolls would be limited to two if the pattern was not broken.