The ring<unk>  abnormality may be limited to as few as 5% of cells, so a screen for chromosomal mosaicism is critical. Newer array technology will not detect the ring chromosome and the standard metaphase chromosome analysis has been recommended. A karyotype analysis examining at least 50 cells should be requested to properly detect mosaicism.
Ring chromosome 20 syndrome
Ring chromosome 14 syndrome
Joubert syndrome
Chromosome 5q deletion syndrome
13q deletion syndrome
Kaufman oculocerebrofacial syndrome
Bardet–Biedl syndrome
2q37 deletion syndrome