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SergiiVlasiuk's solution

to RNA Transcription in the Scala Track

Published at Aug 23 2019 · 0 comments
Test suite

Given a DNA strand, return its RNA complement (per RNA transcription).

Both DNA and RNA strands are a sequence of nucleotides.

The four nucleotides found in DNA are adenine (A), cytosine (C), guanine (G) and thymine (T).

The four nucleotides found in RNA are adenine (A), cytosine (C), guanine (G) and uracil (U).

Given a DNA strand, its transcribed RNA strand is formed by replacing each nucleotide with its complement:

  • G -> C
  • C -> G
  • T -> A
  • A -> U

The Scala exercises assume an SBT project scheme. The exercise solution source should be placed within the exercise directory/src/main/scala. The exercise unit tests can be found within the exercise directory/src/test/scala.

To run the tests simply run the command sbt test in the exercise directory.

For more detailed info about the Scala track see the help page.


Hyperphysics http://hyperphysics.phy-astr.gsu.edu/hbase/Organic/transcription.html

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import org.scalatest.{Matchers, FunSuite}

/** @version 1.2.0 */
class RnaTranscriptionTest extends FunSuite with Matchers {

  test("RNA complement of cytosine is guanine") {
    RnaTranscription.toRna("C") should be(Some("G"))

  test("RNA complement of guanine is cytosine") {
    RnaTranscription.toRna("G") should be(Some("C"))

  test("RNA complement of thymine is adenine") {
    RnaTranscription.toRna("T") should be(Some("A"))

  test("RNA complement of adenine is uracil") {
    RnaTranscription.toRna("A") should be(Some("U"))

  test("RNA complement") {
    RnaTranscription.toRna("ACGTGGTCTTAA") should be(Some("UGCACCAGAAUU"))
import scala.util.Try

object RnaTranscription {
  private final val Complements = Map('G' -> 'C', 'C' -> 'G', 'T' -> 'A', 'A' -> 'U')

  def toRna(dna: String): Option[String] = Try(dna.map(Complements)) toOption

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