Iterates over genotypes (ACGT format).

        Returns:
            tuple: The name of the marker as a string, and its genotypes as a
            :py:class:`numpy.ndarray` (ACGT format).

def iter_acgt_geno(self):
        """Iterates over genotypes (ACGT format).

        Returns:
            tuple: The name of the marker as a string, and its genotypes as a
            :py:class:`numpy.ndarray` (ACGT format).

        """
        # Need to iterate over itself, and modify the actual genotypes
        for i, (marker, geno) in enumerate(self.iter_geno()):
            yield marker, self._allele_encoding[i][geno]