STAGE 1 OF 4

Profile the fragment

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THE BRIEF

Before doing anything clever with a sequence you describe it. You are given one DNA fragment made of the letters A, C, G and T.

Your task. Print two lines:

The number of A, C, G and T bases, in that order, separated by single spaces.
The GC content: the percentage of bases that are G or C, rounded to two decimal places.

Input. One line: the DNA fragment.

Output. Two lines, as described above.

GIVEN INPUT

Your code reads this from standard input (input() or sys.stdin), both here and when it is graded.

AGCTTTTCATTCTGACTGCAACGGGCAATATGTCTCTGTGTGGATTAAAAAAAGAGTGTCTGATAGCAGC

EXPECTED OUTPUT FOR THIS INPUT

20 12 17 21
41.43

SKILLS YOU'LL USE

Stuck? These bank problems practise the same techniques.

Write your code

.ipynb

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Check your understanding

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In double-stranded DNA, which base pairs with adenine (A)?

Guanine (G) Thymine (T) Cytosine (C) Uracil (U)

Why do biologists care about a region's GC content?

G and C make the sequence read faster G-C pairs are held by three hydrogen bonds, so GC-rich DNA is more stable and behaves differently from AT-rich DNA It tells you the length of the gene It is always exactly 50 percent in every organism

Explain and submit

Explain how you counted the bases and how you turned the counts into a GC percentage.

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