Just as there is uniformity in the DNA building block in our world, so too in the entire universe. DNA is a technological marvel, no less!
Aliens are made of organic materials, and although they sometimes use different forms of reproduction, the famous DNA molecule also exists in all alien worlds. DNA is a very successful, reliable, and stable molecule. The double helix and genetic coding are very sophisticated binary codes. Did life on Earth come into being out of thin air? Of course not! The theory of abiogenesis has met with heavy opposition since it is tough to believe that such a sophisticated molecule was created randomly. Crick and Watson, who discovered the molecule of DNA, were struck by the level of sophistication and doubted themselves that it was indeed a random creation of nature.
The apparent philosophical question will always be: Who created the first alien and DNA molecule in the cosmos? Philosophers will answer this. It would certainly be convenient for all religious scholars to say that this is proof that God created everything, including the aliens. In any case, these claims can never be proven, positively or negatively. (Kurt Goodell's mathematical incompleteness and Alan Turing's halting problem)