SAN ANTONIO (Dec. 6, 2012) — A tool called microarray testing can help doctors to more often pinpoint the potential genetic reason for a stillbirth, so that more couples can learn what happened to their babies, a study of 500 stillbirths in San Antonio and four other cities showed.
The study, co-authored by a pathologist and a maternal fetal medicine physician from UT Medicine San Antonio, was published Dec. 6 by The New England Journal of Medicine. UT Medicine is the clinical practice of the School of Medicine at The University of Texas Health Science Center San Antonio.
“Using microarray, we were able to find a potential genetic reason more often than by conventional karyotype,” said UT Medicine maternal-fetal specialist Donald J. Dudley, M.D., professor of obstetrics and gynecology in the School of Medicine at the Health Science Center.
A karyotype is a picture of the chromosomes arrayed in pairs; the chromosomes, which contain genetic information, appear as rod-shaped structures. Karyotyping was developed gradually in the late 1800s and early 1900s. Microarray testing, meanwhile, arranges samples of many genes in a pattern on a glass slide or other surface. The expression of the genes can be measured. Microarrays came into use starting in the mid-1990s.
A karyotype can be obtained from a tiny amount of living tissue, said UT Medicine pathologist Josefine Heim-Hall, M.D., professor of pathology in the School of Medicine. However, the problem with stillbirths is that the cell cultures often fail (the cells are dead or don’t grow well). In 30 percent of cases, karyotyping is not possible.
Microarray does not require live cells, and it detects small genetic deletions and duplications. According to the study, led by the National Institutes of Health, microarray provided results in 87 percent of stillbirth cases.
About 150 of the stillbirth cases were in San Antonio, Dr. Dudley said. He organized a local stillbirth study network consisting of the following clinical partners: University Hospital, Baptist Health System hospitals, Methodist Healthcare System hospitals, CHRISTUS Santa Rosa hospitals, Southwest General Hospital and the former Wilford Hall Medical Center.
Use of microarray testing after stillbirth will continue to expand investigation into genetic causes of stillbirth, Dr. Heim-Hall said.
UT Medicine San Antonio is the clinical practice of the School of Medicine at the UT Health Science Center San Antonio. With more than 700 doctors – all School of Medicine faculty – UT Medicine is the largest medical practice in Central and South Texas. Expertise is in more than 100 medical specialties and subspecialties. Primary care doctors and specialists see patients in private practice at UT Medicine’s flagship clinical home, the Medical Arts & Research Center (MARC), located at 8300 Floyd Curl Drive, San Antonio 78229. Most major health plans are accepted, and UT Medicine physicians also practice at several local and regional hospitals. Call (210) 450-9000 to schedule an appointment, or visit www.UTMedicine.org for a list of clinics and phone numbers.