如何得到给定序列的互补序列以及反向互补序列

用 python 实现如下:

#!/usr/bin/python
# Complementing DNA

my_dna = "ACTGATCGATTACGTATAGTATTTGCTATCATACATATATATCGATGCGTTCAT"
# 由于python 区分大小写，所以先替换成小写可以有效避免后面重复替换的问题。
complement_AT = my_dna.replace("A","t")
complement_TA = complement_AT.replace("T","a")
complement_GC = complement_TA.replace("G","c")
complement_CG = complement_GC.replace("C","g")
# 把所以小写变为大写即可。
complement_DNA = complement_CG.upper()
reverse_complement_DNA = complement_DNA[::-1]  # str[::-1] used to reverse the string

print(complement_DNA)
print(reverse_complement_DNA)

运行结果：

ubuntu$ python3 complement_py3.py 
TGACTAGCTAATGCATATCATAAACGATAGTATGTATATATAGCTACGCAAGTA
ATGAACGCATCGATATATATGTATGATAGCAAATACTATACGTAATCGATCAGT