Question 18M.3.HL.TZ2.b
| Date | May 2018 | Marks available | [Maximum mark: 3] | Reference code | 18M.3.HL.TZ2.b |
| Level | HL | Paper | 3 | Time zone | TZ2 |
| Command term | Analyse | Question number | b | Adapted from | N/A |
A protein expressed by the gene carotene desaturase (CTP1) was introduced into Golden rice (Oryza sativa) through genetic engineering. Bioinformatics were used to determine if the protein sequence matched any allergenic proteins (proteins that trigger an allergic reaction). The table shows the results from the alignment of the CTP1 protein with proteins from moth, soybean and dust mite that are known to be allergenic.
Regulations say that a protein is considered allergenic and unsafe for human consumption if at least 80 amino acids are aligned and there is greater than 35 % identity with any known allergen. Analyse the data provided to consider whether CTP1 is safe for human consumption.
[3]
a. dust mite protein has 45% identity with CTP1 which could be unsafe
b. only 36 aligned amino acids of dust mite protein which is less than the 80 danger limit
c. both moth and soybean protein have less than 35% identity so are considered safe
d. both moth and soybean protein have more than 80 amino acids aligned so could be unsafe
e. CTP1 is not an allergen as it does not fit the criteria for any allergen
OR
CTP1 from the three organisms is not over the safety limit in the two categories so are considered safe
