The eligibility criteria for the BTech in Genetical Engineering suggests that the student must have passed 10+2 with certain percentage (decided by the institute you are taking admission in) in Physics , Chemistry , Biology / Mathematics . So yeah! If you have Biology then you can take admission in the BTech Genetical Engineering but for the admission to any engineering course you have to give some entrance. Now the engineering entrances three subjects such as Physics, chemistry and Mathematics. So you have to clear the Mathematics paper in entrance as the paper for all Engineering courses are the same.

For more information regarding BTech in Genetical Engineering consider the link below:

https://www.careers360.com/courses/genetic-engineering-course

I hope this helps. Wish you a great day!