Clinical findings and cytogenetic analysis of small supernumerary ring chromosomes 7: report of two new cases.
Two new patients, mosaic for a small supernumerary ring chromosome 7 are described. There are only seven published reported concerning supernumerary ring chromosome 7 and we reviewed the previously reported cases in an attempt to establish genotype-phenotype correlations, which are particularly important for genetic counselling and clinical genetics. Our first case was a 20 months old girl who was referred for a mild motor developmental delay, an asymmetric facial appearance, a plagiocephaly and a short nose with anteverted nostrils. Our second case was a 9 years old boy who was referred for a IQ at the lower end of the normal range (? 80), obesity, hyperactivity and some dysmorphic features including hypertelorism and down slanting palpebral fissures. In both cases, chromosome analysis after G and R banding and FISH showed a small ring chromosome 7 in respectively 76% and 50% of consecutively scored metaphases. Both ring chromosomes were labelled by FISH using the Williams Syndrome locus probe (Elastin Gene D7S486). Comparison between these two cases and previously published cases allowed to delineate frequent clinical findings. A mild mental retardation was found in the majority of patients. which is an important data for genetic counselling.
Chantot-Bastaraud
Sandra
S
Service d'Histologie, Biologie de la Reproduction et Cytogénétique (UPMC-EA 1533), Hôpital Tenon (AP-HP), 75020 Paris, France.
Muti
Christine
C
Pipiras
Eva
E
Routon
Marie Claude
MC
Roubergue
Anne
A
Burglen
Lydie
L
Siffroi
Jean Pierre
JP
Simon-Bouy
Brigitte
B
D000015:Abnormalities, Multiple / Q000235:genetics*; D002648:Child; D002871:Chromosome Banding; D025063:Chromosome Disorders / Q000235:genetics*; D002897:Chromosomes, Human, Pair 7 / Q000235:genetics / Q000648:ultrastructure*; D005145:Face / Q000002:abnormalities; D005260:Female; D006801:Humans; D017404:In Situ Hybridization, Fluorescence; D007223:Infant; D008607:Intellectual Disability / Q000235:genetics*; D008297:Male; D009765:Obesity / Q000235:genetics; D010641:Phenotype; D011595:Psychomotor Agitation / Q000235:genetics; D012303:Ring Chromosomes; D014314:Trisomy