Ring autosomes: some unexpected findings.
Ring chromosomes are rare entities, usually associated with phenotypic abnormalities in correlation with the loss of genetic material. There are various breakpoints and sometimes there is a dynamic mosaicism that is reflected in clinical features. Most of the ring chromosomes are de novo occurrences. Our study reflects the experience of three Romanian cytogenetic laboratories in the field of ring chromosomes. We present six cases with ring chromosomes involving chromosomes 5, 13, 18, and 21. All ring chromosomes were identified after birth in children with plurimalformative syndromes. The ring chromosome was present in mosaic form in three cases, and this feature reflects the ring's instability. In case of ring chromosome 5, we report a possible association with oculo-auriculo-vertebral spectrum.
"Grigore T. Popa" University of Medicine and Pharmacy Iasi, Department of Medical Genetics, Iasi, Romania.
L
L
Caba
C
C
Rusu
Plăiaşu
G
G
Gug
M
M
Grămescu
C
C
Bujoran
D
D
Ochiană
M
M
Voloşciuc
R
R
Popescu
E
E
Braha
M
M
Pânzaru
L
L
Butnariu
A
A
Sireteanu
M
M
Covic
Ev
E
Gorduza
Chromosomal instability; Mosaicism; Rare disease; Ring chromosome; Variable phenotype