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We studied monosomy and deletions of chromosome 7 in 208 patients with myeloid disorders; we found 39 patients (19%) with monosomy or deletion of chromosome 7: 24 patients with chromosome 7 deletion and 15 with monosomy 7. In the 24 patients with chromosome 7 deletions, studied with copy-number variants, short-tandem repeats, microsatellites, single nucleotide polymorphisms, and deletion polymorphisms, the most common deleted region was 7q31.1 (20 patients). Deletion polymorphism studies performed in these 20 patients showed an interstitial deletion of at least 140 kilobase in 6 patients; the deletion spans between the genes forkhead box P2 and Myo D family inhibitor domain containing. Because both genes do not seem to be involved in leukogenesis, we suggest to look carefully into this deletion for the presence of tumor suppressor genes and microRNAs. [ABSTRACT FROM AUTHOR]

Abstract: Silver–Russell syndrome (SRS) is a heterogeneous syndrome which is characterized by severe intrauterine and postnatal growth retardation and typical dysmorphic features. In 5–10% of SRS patients, a maternal uniparental disomy of chromosome 7 (UPD7) can be detected. We describe a 4.5-y old boy. Physical examination at the age of 4.5 y was remarkable for small stature, relatively big head, triangular face, broad forehead, pointed chin and clinodactyly. He had hypopigmented macules on his back with no evidence of asymmetry/hemihypertrophy. Clinical diagnosis of Silver–Russell syndrome was made. Maternal UPD of chromosome 7 was found, confirming the diagnosis. Along with the clinical findings that are described in this syndrome he had moderate developmental delay which is not commonly found in these patients and underwent an autistic regression around the age of 2 years. This association has only once been described before in this syndrome. A possible explanation is that the autism is not a part of SRS but is due to the UPD. Our case suggests an association of autistic regression with a locus on chromosome 7. [Copyright &y& Elsevier]

Our aim is to use information from cytogenetic anomalies to identify candidate genes for autism.We have identified a male patient with mental retardation and autism who has a balanced translocation involving chromosomes 6 and 7, described as t(6;7)(p11-p12;q22). This translocation was inherited from an apparently normal father.Using fluorescence in situ hybridization, we have localized the breakpoints on both the chromosomes; and using bioinformatic genomic analysis, we have identified a number of potential candidate genes at these loci. These include the neural pentraxin 2 gene, NPTX2, and a novel gene encoding a transmembrane protein, TMEM130, which contains a polycystic kidney domain on 7q22. On 6p12 the breakpoint directly interrupts isoform 2 of the human homologue of the mouse dystonin gene. We also performed a 250 K single nucleotide polymorphism microarray analysis and comparative genomic hybridization using a bacterial artificial chromosome microarray to look for minor genomic deletions or duplications in the proband's DNA. The single nucleotide polymorphism microarray analysis identified a number of copy number variants, remote from the translocation breakpoints, containing potential candidate genes.It is conceivable that one or more of the copy number variant regions or either of the two breakpoint locations and the dystonin gene, in particular, may be a new locus for a form of mental retardation, which may also include autistic features. [ABSTRACT FROM AUTHOR]

Silver-Russell syndrome (SRS) is a clinically heterogeneous syndrome characterized by intra-uterine and postnatal growth retardation with spared cranial growth, dysmorphic features and frequent body asymmetry. Various cytogenetic abnormalities have been described in a small number of SRS or SRS-like cases involving chromosomes 7, 8, 11, 15, 17 and 18. However, until recent data became available involving imprinted genes on chromosome 7 and chromosome 11p15, the molecular cause of the syndrome was unknown in most cases. Genomic imprinting is the best example of transcriptional control of genes by epigenetic modifications. Many imprinted genes play key roles in fetal and placental growth and behaviour. This is illustrated in SRS, which can now be considered as a new imprinting disease model. These new findings in the pathophysiology of SRS allow long-term follow-up studies to be performed based on molecular diagnosis. This could help to define appropriate clinical guidelines regarding growth and feeding difficulties. [Copyright &y& Elsevier]