# Sequences

The `Sequence` object provides generic biological sequence manipulation functions, plus functions that are critical for the `evolve` module calculations.

## Generic molecular types

Sequence properties are affected by the moltype you specify. The default type for a sequence is `"text"`.

In some circumstances you can also have a `"bytes"` moltype, which I’ll explicitly construct here.

## DNA and RNA sequences

### Creating a DNA sequence from a string

Sequence properties are affected by the moltype you specify. Here we specify the `DNA` `MolType`.

### Creating a RNA sequence from a string

### Converting to FASTA format

### Convert a RNA sequence to FASTA format

### Creating a named sequence

You can also use a convenience `make_seq()` function, providing the moltype as a string.

### Setting or changing the name of a sequence

### Complementing a DNA sequence

### Reverse complementing a DNA sequence

### Translate a `DnaSequence` to protein

### Converting a DNA sequence to RNA

### Convert an RNA sequence to DNA

### Testing complementarity

### Joining two DNA sequences

### Slicing DNA sequences

### Getting 3rd positions from codons

The easiest approach is to work off the `cogent3` `ArrayAlignment` object.

### Getting 1st and 2nd positions from codons

In this instance we can use features.

### Return a randomized version of the sequence

### Remove gaps from a sequence

previous

Loading a sequence from a file

next

Protein sequences