This is my entry for 
If Santa Claus was real, in what sense can he be real among his tales, I won't joke about he got world class surveillance child stalking systems pairing with parents and teachers to monitor all the children world wide. (but this is somehow plausible, otherwise why he need to live in North Pole?? only the cold weather there can cool his super computers and stuff!!)
The most likely real part of Santa Claus must be Rudolph!!
Rudolph the Red nose reindeer, had a very shiny nose, and if you ever saw it you would even say it glows~
We all know how this song is sang, and according to the lyrics, Rudolph has a possibly red glowing nose which can guide Santa in the night. Very obviously Rudolph is a Genetic Modified Organism (GMO), with its nose tissue being replaced by Red light emitting cells.
Santa is a genetic engineer
Santa is also a genetics engineering apart from being a computer expert in world wide surveillance. And here is how he made Rudolph:
First he collected Nasal tissue samples from the none- light emitting Rudolph, those biopsy cells (eg. Skin fibroblasts) were incubated with reprogramming factors to induce the pluripotency. Those Induced Pluripotent Stem cells (IPS cells) are collected, gene editing via crispr cas 9 will allow the editing of the reindeer genome.
Red fluorescent protein (along with other photophore system, such as that from Malacosteus, Aristostomias, or Pachystomias) or red color luciferase gene cassettes (eg. from Phrixothrix) could be adopted. Those transgenic IPS cells could be grown on the back of Rudolph until they differentiate back to a nose like structure. This nose like structure will be readily transplantable to replace the existing nasal structures of Rudolph, with new Red glowing functions. (at the cost of losing normal nasal functions, but it glows!!).
Yet there is another catch!! Red light does not penetrate the dark as well as we think, this is why military night operations uses red flash light to read maps, apart from the benefit of not bleaching your eyes in the dark. And if Rudolph does glows so red that it shines, then I think we will all be able to spot Santa flying across the sky.
Rudolph nose 2.0 should be Infrared emitting
Lighting up the sky each X'mas with red light will make Santa easily detectable by nake eyes, that's why, Rudolph was in real genetically engineered as Infrared spectrum wavelength emitting from its nose rather than red visible spectrum wavelength. This pairing Santa Claus' infrared night goggles or any digital camera with IR filters removed could easily navigate the sky without stirring a red flare in the sky during X'mas time!!! This is actually more energy efficient as infrared night goggles requires small amount of infrared light source to light up the sky, compare to the true red light needed to lead Santa's way.
A woman grows a nose tumor on her spine post stemcell treatment and some deep water organism employs near infrared light for such purpose, this allows modern day Santa to easily employ such protein tools for GMO reindeers~
Sources:
http://biolum.eemb.ucsb.edu/organism/dragon.html
https://lifescienceexplore.wordpress.com/2013/12/31/10-awesome-land-creatures-that-can-glow/
https://ipscell.com/2014/07/woman-grows-nose-tumor-in-spine-after-stem-cell-treatment-perspectives/
Photo sources:
pixabay.com