We report a 2(3/12)-year-old boy with a constitutional interstitial deletion of 5q,46,XY,del(5)(q23.3q31.2) de novo. Clinical manifestations in this patient included failure to thrive, psychomotor retardation, mild facial dysmorphic features, and long and slender fingers and toes. The precise location and extent (9.5 Mb) of the deletion was determined by fluorescence in situ hybridization (FISH) using 19 YAC and BAC clones. Comparison of the present patient with six other patients with deletions of chromosomal bands 5q22-5q31 allowed further delineation of a constitutional del5q22q31 syndrome. The main features of this syndrome are psychomotor retardation, failure to thrive, hypotonia, hypoplastic muscles, cleft or high arched palate, low-set and dysplastic ears, flat nasal bridge, downslanting palpebral fissures, hypertelorism, anteverted nostrils, and micro- and/or retrognathia.

Interstitial deletions of 10q are rare, and only one patient with a deletion confined to chromosome band 10q22 has been reported so far. We report on a 2 6/12-year-old girl with a constitutional interstitial deletion of one homologue of 10q [karyotype: 46,XX,del(10)(q22.2q22.3)de novo]. Our patient had muscular hypotonia, developmental delay, growth retardation, mild facial dysmorphism, and hypoplastic labia minora. The precise location and extent (3.6 Mb) of the deletion was determined by fluorescence in situ hybridization (FISH) using 16 YAC and BAC clones. The clinical features in our patient are remarkably similar to the previously reported patient with a 10q22.2 deletion.

We report on a 12-month-old boy with pre and post-natal growth retardation, triangular face and mild psychomotor retardation. Karyotyping revealed a supernumerary marker chromosome (SMC) in 36% of cells. Using fluorescence in situ hybridization and BAC clones, the supernumerary marker chromosome was found to be a highly deleted chromosome 7 with breakpoints within the pericentric euchromatin (partial trisomy 7). Microsatellite typing indicated maternal uniparental disomy of chromosome 7 (matUPD7). The patient showed only few signs of the Silver-Russell syndrome. He therefore reflects the mild end of the phenotypic spectrum in patients with matUPD7. The case supports the argument that karyotyping is warranted in patients with short stature and only few additional features, and that UPD studies are required in patients with a SMC(7). Considering that the SMC(7) contributed very little, if any, to the phenotype of this boy, we propose that UPD7 studies should be carried out in children with pre- and postnatal growth retardation of unknown cause even in the absence of a SMC.