/** * {@inheritDoc} */ public function getChildren() { $children = parent::getChildren(); foreach ($this->exons as $exon) { if (!$children->contains($exon)) { $children->add($exon); } } foreach ($this->introns as $intron) { if (!$children->contains($intron)) { $children->add($intron); } } foreach ($this->mRNAs as $mRNA) { if (!$children->contains($mRNA)) { $children->add($mRNA); } } return $children; }