Five cases of supernumerary small ring chromosomes 1: heterogeneity and genotype-phenotype correlation.
Genetic counselling of patients with small supernumerary ring chromosomes (sSRCs) can be difficult, especially in prenatal testing, due to the complexity in establishing a karyotype-phenotype correlation. In fact, it has been estimated that about 10% of extra ring(1) chromosomes are associated with an unremarkable phenotype. We report on five new cases of extra ring chromosomes(1) manifesting different clinical outcome. One case was familial, segregating from a mother with mosaic karyotype, while the others were de novo. Ring chromosomes were characterised by FISH. In three subjects the involvement of the same euchromatic 1p region was demonstrated. Present observations corroborate previous results and provide some insight into the identification of the harmless ring(1) structures.
Bernardini
Laura
L
Ospedale Casa Sollievo della Sofferenza, San Giovanni Rotondo e Istituto CSS-Mendel, Roma, Italy.
Capalbo
Anna
A
D'Avanzo
Maria Gabriella
MG
Torrente
Isabella
I
Grammatico
Paola
P
Dell'Edera
Domenico
D
Cavalcanti
Denise Pontes
DP
Novelli
Antonio
A
Dallapiccola
Bruno
B
D002871:Chromosome Banding; D002874:Chromosome Mapping; D002878:Chromosomes, Human, Pair 1; D005260:Female; D005817:Genetic Counseling; D018740:Genetic Heterogeneity; D005819:Genetic Markers; D005838:Genotype; D006801:Humans; D017404:In Situ Hybridization, Fluorescence; D007231:Infant, Newborn; D007621:Karyotyping; D008297:Male; D018895:Microsatellite Repeats; D009030:Mosaicism; D010641:Phenotype; D011247:Pregnancy; D012303:Ring Chromosomes; D024182:Uniparental Disomy
D005819:Genetic Markers