Keep in mind, we're talking Missions, which has specific rules and guidelines that have to be followed if you want to play take your character into other Missions events, such as at cons.
Ahh, ok. Here we go. Found the relevant texts that solves the problem.
Runner's Companion, p. 73
The first step when creating a changeling character is to choose a normal metatype (human, elf, dwarf, ork, or troll), metavariant (p. 46), or, contingent on gamemaster approval, a Non-Metahuman sapient. As with a regular character, this choice defines his natural attribute minimums and maximums, as well as setting augmented maximums (see Building a Shadowrunner, p. 72, SR4).
Shadowrun Missions Season Four FAQ, p. 5
CAN I USE OPTIONAL RULE (FILL IN THE BLANK)?
Unless this FAQ states otherwise, no. To give every Missions player the same game experience and maintain campaign balance, we
generally avoid using any rule that is listed as optional.
The key here is the phrase "Contigent upon gamemaster approval". Anything that is subject to GM fiat in this way is considered an optional rule. So the FAQ blanket rule applies. Anything considered optional that the FAQ doesn't specifically say "Yes, this is allowed" is disallowed.
I apologize, since this means I'm going back on my earlier statement. I had missed the opening part of "Creating a Changeling" on page 73.
Bull