title: Subtle trisomy 12q24.3 and subtle monosomy 22q13.3: three new cases and review.
abstract: The high resolution G-bands (850 bands) karyotype have made it possible to identify small chromosome anomalies (5 megabases) which are now microscopically visible. New techniques have been improved, such as the Fluorescent in situ hybridization (FISH) with subtelomeric probes, which can be employed to detect cryptic chromosome alterations not visible microscopically. We present three cases which had been remitted for a high resolution karyotype. The high resolution G-band karyotype and the FISH techniques led us to conclude that the three cases were carriers of a similar subtle chromosomal alteration. Case I is a new born female with developmental and psychomotor delay, hypotonia, and long limbs with arachnodactily. A high resolution G-band karyotype showed an abnormal chromosome 22. FISH techniques confirmed a der(22)t(12;22)(q24.31;q13.3). Case II is a 12-year-old girl, with growth retardation, long shaped face with thick eyebrows, smooth philtrum, and thin upper lip with severe mental retardation (still no language), with a phenotype very similar to that of his sister: long shaped face, thick eyebrows, smooth philtrum, and thin upper lip. A high resolution G-band karyotype also showed in Case II and III an abnormal chromosome 22, studied by FISH techniques which confirmed a der(22)t(12;22)(q24.3;q13.3) in both cases.
authors.affiliation: Estudio Colaborativo Español de Malformaciones Congénitas (ECEMC) del Centro de Investigación sobre Anomalías Congénitas (CIAC), Instituto de Salud Carlos III, Ministerio de Sanidad y Consumo, Madrid, Spain. laura@isciii.es
authors.forename: Laura
authors.initials: L
authors.lastname: Rodríguez
authors.forename: Nieves
authors.initials: N
authors.lastname: Martínez Guardia
authors.forename: Christian
authors.initials: C
authors.lastname: Herens
authors.forename: Mauricette
authors.initials: M
authors.lastname: Jamar
authors.forename: Alain
authors.initials: A
authors.lastname: Verloes
authors.forename: Fermina
authors.initials: F
authors.lastname: López
authors.forename: José
authors.initials: J
authors.lastname: Santos Muñoz
authors.forename: María Luisa
authors.initials: ML
authors.lastname: Martínez-Frías
mesh_terms: D000015:Abnormalities, Multiple / Q000235:genetics*; D002675:Child, Preschool; D002869:Chromosome Aberrations; D002881:Chromosomes, Human, Pair 12; D002892:Chromosomes, Human, Pair 22; D005260:Female; D006801:Humans; D017404:In Situ Hybridization, Fluorescence; D007223:Infant; D007621:Karyotyping; D008297:Male; D009006:Monosomy; D014314:Trisomy