Board Thread:Questions and Answers/@comment-217.118.81.27-20130902124829/@comment-1672596-20151208161846

Bluerock wrote: Those views are examined, sure, but MGS1 ultimately pushed the exact opposite idea, that one shouldn't be ruled by their genes. The inability to have biological children due to cyborg mods would not be a deal breaker for all people.

That may have been the intention, but it didn't push the opposite idea. In fact, its YMMV page even noted that its intended Aesop was broken in the ending after Liquid dies from FOXDIE:

"Broken Aesop: The game explicitly delivers its "don't let yourself be ruled by your genes" message during a nice long shot of Liquid Snake's corpse, who was killed by a "smart" virus that targets people based on their DNA."

Source: http://tvtropes.org/pmwiki/pmwiki.php/YMMV/MetalGearSolid (Broken Aesop section)

Under Broken Aesop itself, it even mentions that MGS4 conflicted with that bit with the mention of his clone degeneration from LET (technically, that bit started with MGS2, but still...):

"Metal Gear Solid explicitly delivers its "don't let yourself be ruled by your genes" message during a nice long shot of Liquid Snake's corpse, who was killed by FOXDIE, a virus that targets people based on their DNA. It gets worse as the series progresses, where in the fourth game Solid Snake is dying of old age at 42 because, yep, that's in his genes."

Source: http://tvtropes.org/pmwiki/pmwiki.php/BrokenAesop/VideoGames