Going by what I read here:
"Tyrosinase (tie-ROW-sin-ace) is the major enzyme involved in the formation of melanin pigment. Tyrosinase is responsible for converting tyrosine to DOPA and on to dopaquinone (dopa-QUIN-own). The dopaquinone then forms black-brown eumelanin or red-yellow pheomelanin. The tyrosinase enzyme is made by the tyrosinase gene on chromosome 11, and alterations (also called mutations) of this gene can produce one type of albinism because the tyrosinase enzyme made by the altered gene does not work correctly."

It would stand to believe all boa albinos seem to be T positive because they have the ability to produce red and yellow coloration.

Quote taken from: http://albinism.med.umn.edu/newfacts.htm#whatis
The link that Tom Burke posted below.

[ Hide Replies ]

• Are all albinos T positive??? - vcaruso15, Sun Jun 3 18:08:37 2007
• RE: Are all albinos T positive??? - Tom Burke, Sun Jun 3 20:04:17 2007
• RE: Are all albinos T positive??? - wstreps, Sun Jun 3 21:18:08 2007
• Good post Ernie! n/p - giantkeeper, Sun Jun 3 21:30:26 2007
• I don't neccessarily agree - Tom Burke, Mon Jun 4 15:38:14 2007
• RE: Are all albinos T positive??? - Paul Hollander, Mon Jun 4 13:43:56 2007
• RE: Are all albinos T positive??? - Tom Burke, Mon Jun 4 15:26:47 2007
• Right, ... - Paul Hollander, Mon Jun 4 16:50:12 2007