Biomedical subjects

K D McGowan

Publications and source records attributed to K D McGowan.

5 recordsLinked to original sources

PubMed1996

Issues in the genetic assessment of predispositions for familial breast and ovarian cancer.

A rapid development in technology has enabled predictive testing for cancer suceptibility genes, such as BRCA1 and BRCA2. Already biotechnology companies and a number of university-based researchers are establishing service laboratories for the analysis of cancer predispositions. It is critical that high standards be established and maintained when conducting DNA testing, which should be performed in a research setting with proper Institutional Review Board approval. A cancer risk assessment programme should include the involvement of various experts in genetics, oncology, psychiatry and counselling. The legal, ethical and social issues involved in screening and testing for cancer predisposition genes are complex. Genetic counselling of subjects undergoing testing is needed to inform them of the potential risks as well as the potential benefits associated with presymptomatic testing.

Breast Neoplasms↗

PubMed1994

Osteogenesis imperfecta and campomelic dysplasia: difficulties in prenatal diagnosis.

The classic features of osteogenesis imperfecta and campomelic dysplasia typically are so specific that these two forms of skeletal dysplasia are among the few that can be diagnosed in the second trimester of pregnancy. We report a series of seven examples of osteogenesis imperfecta and one example of campomelic dwarfism to illustrate the difficulty of differentiating these two disorders in utero. The prenatal sonographic findings in three of the osteogenesis imperfecta cases mimicked campomelic dwarfism, whereas the case of campomelic dwarfism was antenatally diagnosed as osteogenesis imperfecta.

Adolescent↗

PubMed1993

Preimplantation prenatal diagnosis.

Preimplantation prenatal diagnosis refers to the application of molecular genetic techniques to the assessment of gametes before conception or to early embryos before implantation. Such techniques could allow couples at significant risk for a variety of known genetic diseases to use assisted reproductive technology in achieving pregnancies that are free of the genetic disorder in question. The techniques, their risks, benefits, limitations, and potential applications are described, and recent experiences with human pregnancies are reviewed.

DNA↗

PubMed1992

Plasma glutamine concentration: a guide in the management of urea cycle disorders.

Because increases in plasma glutamine concentrations are almost always associated with hyperammonemia in patients with urea cycle disorders, we determined the correlation between these two variables for 2 years in a child with ornithine transcarbamylase deficiency. A correlation coefficient of 0.77 (p less than 0.0001) was found. Hyperammonemia was rarely observed when plasma glutamine levels were near normal. These data suggest that one goal of therapy is the maintenance of plasma glutamine levels at or near normal values.

Amino Acid Metabolism, Inborn Errors↗

PubMed1991

Amniocentesis and chorionic villus sampling.

Amniocentesis and chorionic villus sampling (CVS) remain the most commonly used invasive prenatal diagnostic procedures. Recent reports on early amniocentesis demonstrate its application to the prenatal detection of certain biochemical disorders. However, its role in the evaluation of open fetal defects of the neural tube or ventral wall is still under investigation. The fact that many reports concerning early amniocentesis include a majority of patients beyond 11 to 12 weeks' gestation, thus placing the procedure outside the first trimester, make comparisons with CVS (usually performed between 9 and 11 weeks) problematic. The role of midtrimester amniocentesis in evaluating elevations of maternal serum alpha-fetoprotein, following a normal ultrasonographic examination performed specifically to detect fetal anomalies, is under scrutiny. It appears that risk adjustment may be appropriate following a normal scan, and prior to invasive procedures, but each center's recommendation to a given patient will depend on the expertise of the individual sonographer, as well as the quality of examination. CVS has gained acceptance as a safe first-trimester means of prenatal diagnosis, with increasing applications in the later stages of pregnancy. Chromosomal mosaicism detected by CVS may represent a phenomenon inherent to placental tissue; questions remain regarding mosaicism as a potential marker for increased pregnancy loss. Comparisons between the transcervical and transabdominal routes are reviewed, with equivalent results regarding safety and efficacy. Recent evaluations of fetomaternal transfusion following CVS are also described.

Amniocentesis↗