A new biological and clinical resource for research into pregnancy complications: The Baby Bio Bank.

About 20% of pregnancies are affected by some form of complication. Research has shown that anomalies in implantation, development, and growth of the fetus; ineffective nutrient exchange between mother and fetus due to placental dysfunction; and maternal problems such as hypertension or infection during pregnancy can all lead to adverse pregnancy outcomes. However, the molecular aetiology of such events remains poorly understood.

Trans effects of chromosome aneuploidies on DNA methylation patterns in human Down syndrome and mouse models.

Background: Trisomy 21 causes Down syndrome (DS), but the mechanisms by which the extra chromosome leads to deficient intellectual and immune function are not well understood.

Results: Here, we profile CpG methylation in DS and control cerebral and cerebellar cortex of adults and cerebrum of fetuses. We purify neuronal and non-neuronal nuclei and T lymphocytes and find biologically relevant genes with DS-specific methylation (DS-DM) in each of these cell types.

The role and interaction of imprinted genes in human fetal growth.

Identifying the genetic input for fetal growth will help to understand common, serious complications of pregnancy such as fetal growth restriction. Genomic imprinting is an epigenetic process that silences one parental allele, resulting in monoallelic expression. Imprinted genes are important in mammalian fetal growth and development.

Paternally expressed, imprinted insulin-like growth factor-2 in chorionic villi correlates significantly with birth weight.

Context: Fetal growth involves highly complex molecular pathways. IGF2 is a key paternally expressed growth hormone that is critical for in utero growth in mice. Its role in human fetal growth has remained ambiguous, as it has only been studied in term tissues.

Imprinted chromatin around DIRAS3 regulates alternative splicing of GNG12-AS1, a long noncoding RNA.

Imprinted gene clusters are regulated by long noncoding RNAs (lncRNAs), CCCTC binding factor (CTCF)-mediated boundaries, and DNA methylation. DIRAS3 (also known as ARH1 or NOEY1) is an imprinted gene encoding a protein belonging to the RAS superfamily of GTPases and is located within an intron of a lncRNA called GNG12-AS1. In this study, we investigated whether GNG12-AS1 is imprinted and coregulated with DIRAS3.

Multiple congenital melanocytic nevi and neurocutaneous melanosis are caused by postzygotic mutations in codon 61 of NRAS.

Congenital melanocytic nevi (CMN) can be associated with neurological abnormalities and an increased risk of melanoma. Mutations in NRAS, BRAF, and Tp53 have been described in individual CMN samples; however, their role in the pathogenesis of multiple CMN within the same subject and development of associated features has not been clear. We hypothesized that a single postzygotic mutation in NRAS could be responsible for multiple CMN in the same individual, as well as for melanocytic and nonmelanocytic central nervous system (CNS) lesions.

Exploring the spectrum of 3-M syndrome, a primordial short stature disorder of disrupted ubiquitination.

3-M syndrome is an autosomal recessive primordial growth disorder characterized by small birth size and post-natal growth restriction associated with a spectrum of minor anomalies (including a triangular-shaped face, flat cheeks, full lips, short chest and prominent fleshy heels). Unlike many other primordial short stature syndromes, intelligence is normal and there is no other major system involvement, indicating that 3-M is predominantly a growth-related condition. From an endocrine perspective, serum GH levels are usually normal and IGF-I normal or low, while growth response to rhGH therapy is variable but typically poor.

Germline melanocortin-1-receptor genotype is associated with severity of cutaneous phenotype in congenital melanocytic nevi: a role for MC1R in human fetal development.

Congenital melanocytic nevi (CMN) are pigmented birthmarks that affect up to 80% of the skin surface area. The increased frequency of CMN in families of severely affected individuals is suggestive of a predisposing germline genotype. We noted a high prevalence of red hair in affected families, and considered a role for MC1R in this condition.

Maternal inheritance of a promoter variant in the imprinted PHLDA2 gene significantly increases birth weight.

Birth weight is an important indicator of both perinatal and adult health, but little is known about the genetic factors contributing to its variability. Intrauterine growth restriction is a leading cause of perinatal morbidity and mortality and is also associated with adult disease. A significant correlation has been reported between lower birth weight and increased expression of the maternal PHLDA2 allele in term placenta (the normal imprinting pattern was maintained).

The growth hormone receptor gene deleted for exon three (GHRd3) polymorphism is associated with birth and placental weight.

Context: Human growth hormone receptor (GHR) transcripts have two isoforms, full-length (GHRfl) or exon 3 deleted (GHRd3). An association of these isoforms has been found with small for gestational age (SGA) infants but does not influence adult height. The role of this polymorphism in the birth size spectrum in the general population is unclear.

The primate-specific microRNA gene cluster (C19MC) is imprinted in the placenta.

Imprinted genes play crucial roles in mammalian development and disruption of their expression is associated with many human disorders including tumourigenesis; yet, the actual number of imprinted genes in the human genome remains a matter of debate. Here, we report on the unexpected finding that the chromosome 19 microRNA cluster (C19MC), the largest human microRNA gene cluster discovered so far, is regulated by genomic imprinting with only the paternally inherited allele being expressed in the placenta. DNA methylation profiling identified a differentially methylated region (C19MC-DMR1) that overlaps an upstream CpG-rich promoter region associated with short tandem repeats.

High-throughput analysis of candidate imprinted genes and allele-specific gene expression in the human term placenta.

Background: Imprinted genes show expression from one parental allele only and are important for development and behaviour. This extreme mode of allelic imbalance has been described for approximately 56 human genes. Imprinting status is often disrupted in cancer and dysmorphic syndromes.

Somatically acquired hypomethylation of IGF2 in breast and colorectal cancer.

The imprinted insulin-like growth factor 2 (IGF2) gene is expressed predominantly from the paternal allele. Loss of imprinting (LOI) associated with hypomethylation at the promoter proximal sequence (DMR0) of the IGF2 gene was proposed as a predisposing constitutive risk biomarker for colorectal cancer. We used pyrosequencing to assess whether IGF2 DMR0 methylation is either present constitutively prior to cancer or whether it is acquired tissue-specifically after the onset of cancer.

Identification of the imprinted KLF14 transcription factor undergoing human-specific accelerated evolution.

Imprinted genes are expressed in a parent-of-origin manner and are located in clusters throughout the genome. Aberrations in the expression of imprinted genes on human Chromosome 7 have been suggested to play a role in the etiologies of Russell-Silver Syndrome and autism. We describe the imprinting of KLF14, an intronless member of the Krüppel-like family of transcription factors located at Chromosome 7q32.

Skin-homing CD8+ T lymphocytes show preferential growth in vitro and suppress CD4+ T-cell proliferation in patients with early stages of cutaneous T-cell lymphoma.

A total of 27 T-lymphocyte cell strains were established from skin biopsies of 24 patients with various stages of cutaneous T-cell lymphoma (CTCL) by addition of the T-cell growth factors interleukin (IL)-2 and IL-4. Cellular proliferation and phenotypic changes were measured over 3 months in culture, and T-cell clones were studied using T-cell receptor-? re-arrangement techniques. An average outgrowth of 134 million T-lymphocytes from a 4-mm skin biopsy was observed over 2 months.