 Non-coding RNA (ncRNA ) presents a challenge for homology detection, as the primary sequence is often poorly conserved and de novo structure prediction remains difficult.
<meaning-changed>  Non-coding RNA (ncRNA ) presents a challenge for homology detection, as the primary sequence is often poorly conserved and de novo structure prediction remains difficult.
 Non-coding RNA (ncRNA ) presents a challenge for homology detection, as the primary sequence is often poorly conserved and de novo secondary structure prediction and search remains difficult.