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Presents the detection of human novel developmental genes in clone DNA derived from replicate individual preimplantation embryos. Implication of the differential display of the cloned DNA preparations; Variation in patterns of gene expression; Explanations for the variation.

Examines the transcripts of homeobox-containing genes present in cDNA libraries generated from human unfertilized oocytes and preimplantation embryos. Cloning of oocyte fragments; DNA sequence analysis; Homeobox gene expression.

Describes the fundamental features of X-chromosome inactivation (XCI) and other developments in the molecular analyses and characterization of the X gene in human and mice development. Overview of the XCI and genomic imprinting; Discussion on the relationship of XCI and deoxyribonucleic methylation; Conclusions.

We have developed a new procedure, called cell recycling, which combines the two powerful techniques of polymerase chain reaction (PCR) and fluorescent in-situ hybridization (FISH) on the same single cell. A fixed cell is used as the DNA template for PCR, prior to the FISH analysis. Using single blastomeres from mouse embryos as a model system, cell recycling procedures detect the single-copy β-haemoglobin gene sequence at an efficiency of 70% as well as sex chromosome constitution at an efficiency of 74% in the same single cell. Cell recycling will increase the success rate of pregnancy following preimplantation diagnosis for a specific gene defect by identifying embryos with chromosomal abnormalities and eliminating them from the transfer procedure. [ABSTRACT FROM PUBLISHER]

A highly sensitive biochemical microassay has been developed for adenosine deaminase (ADA; EC 3.5.4.4), the enzyme deficient in ∼20% of cases of severe combined immunodeficiency disease (SCID). The microassay is capable of detecting femtomolar amounts of reaction product in a single blastomere from a mouse 8-cell embryo and thus is sensitive enough to be considered for the possible prehnplantation diagnosis of SCID in human embryos. [ABSTRACT FROM PUBLISHER]

Investigates the expression of olfactory receptor genes in human primordial germ cells. Amino acid sequences of olfactory receptor proteins; Mechanism of chemotaxis; Structure of olfactory receptor genes; Gene cloning; Role of olfactory receptors in the primordial germ cell migration.

In mammals, primordial germ cells (PGCs) are first observed in the extraembryonic mesoderm from where they migrate through the hindgut and its mesentery to the genital ridge to colonize the developing gonads. Soon after reaching the gonads, the female PGCs enter meiosis, while the male PGCs are arrested in mitosis and enter meiosis postnatally. To gain an insight into the molecular events controlling human germ cell development, we determined specific profiles of gene expression using cDNA prepared from PGCs isolated from male and female fetal gonads at 10 weeks gestation, when female PGCs start to enter meiosis. The identity of the isolated PGCs, and the cDNA molecules prepared from them, was confirmed respectively, by alkaline phosphatase staining and by the presence of transcripts of OCT4, a marker gene for PGCs and pluripotent stem cells in mice. Using differential display to compare the profiles of gene expression of male and female germ cells with each other and with that of a whole 10 week old fetus, we have identified eight transcripts differentially expressed in male and/or female germ cells. Among these transcripts, we have identified a member of the olfactory receptor gene family, which contains genes known to be germline-specific in the dog and possibly associated with chemotactic function. Another transcript is common to a previously isolated sequence from the human testis and we have extended this sequence towards the 5′ end for partial characterization. The germline-specific sequences also include two novel sequences not represented in the databases. These findings are highly encouraging for the elucidation of the genetic programming of male and female germ line development. [ABSTRACT FROM AUTHOR]

Purpose: Cancer cells recapitulate many behaviors of pluripotent embryonic cells such as unlimited proliferation, and the capacity to self-renew and to migrate. Embryo-cancer sequence A (ECSA), later named developmental pluripotency associated-2 (DPPA2), is an embryonic gene initially isolated from pluripotent human preimplantation embryos. We hypothesized that ECSA/DPPA2 would be quiescent in most normal tissues but expressed in cancers and may therefore be a useful target for immunotherapy., Experimental Design: ECSA/DPPA2 expression was examined in a panel of normal and tumor tissue by reverse transcription PCR, quantitative real-time PCR, and immunohistochemistry. A panel of 110 non-small cell lung cancers (NSCLC) were further investigated for the presence of ECSA/DPPA2 transcripts and several cancer testis antigens (CTA). Sera from 104 patients were analyzed for spontaneous ECSA/DPPA2 antibody production by ELISA and Western blot., Results: ECSA/DPPA2 transcripts were limited to normal testis, placenta, bone marrow, thymus, and kidney but expressed in a variety of tumors most notably in 30% of NSCLC. Enrichment for CTAs in ECSA/DPPA2-positive NSCLC was observed. Immunohistochemistry confirmed nuclear and cytoplasmic localization in subpopulations of cells with coexpression of the CTA MAGE-A3. Antibodies to recombinant ECSA/DPPA2 protein were detected in the sera of 4 of 104 patients with NSCLC but not in healthy controls., Conclusions: The restricted expression in normal tissues, expression in tumors with coexpression of CTAs, and spontaneous immunogenicity indicate that ECSA/DPPA2 is a promising target for antigen-specific immunotherapy in NSCLC.