Inconsistencies in pedigree symbols in human genetics publications: a need for standardization.

To determine consistency in usage of pedigree symbols by genetics professionals, we reviewed pedigrees printed in 10 human genetic and medical journals and 24 medical genetics textbooks. We found no consistent symbolization for common situations such as pregnancy, spontaneous abortion, death, or test results. Inconsistency in pedigree design can create difficulties in the interpretation of family studies and detract from the pedigree's basic strength of simple and accurate communication of medical information. We recommend the development of standard pedigree symbols, and their incorporation into genetic publications, professional genetics training programs, pedigree software programs, and genetic board examinations.

Diffuse mesangial sclerosis in a fetus.

An 18-week fetus was born following termination of pregnancy by prostaglandin induction. Pregnancy was terminated because of elevated maternal serum alpha-fetoprotein and ultrasonographic evidence of severe oligohydramnios, intrauterine growth retardation, non-visualization of the bladder, dolichocephaly and possible mild hydrocephalus. Pathologic examination disclosed diffuse mesangial sclerosis and histologic evidence of the nephrotic syndrome. To our knowledge this is the first reported example of ante-natal diffuse mesangial sclerosis; of fetal congenital nephrosis other than Finnish type; and of fetal congenital nephrosis with prominent glomerular lesions.

Importance of accurate diagnosis in counseling for neural tube defects diagnosed prenatally.

In cases of fetal neural tube defects (NTD), termination of pregnancy without ascertainment of specific etiology may lead to provision of incorrect recurrence risks and erroneous diagnosis in future pregnancies. Four patients are presented who illustrate the etiologic diversity of neural tube defects. The patients were referred for prenatal diagnosis because of elevated maternal serum alphafetoprotein (AFP). All four chose pregnancy termination. Diagnostic methods included fetal ultrasound, amniocentesis for fetal karyotyping and amniotic fluid AFP/acetylcholinesterase (AChE) and/or fetal karyotyping after delivery, and dysmorphology evaluation of the fetus after intact delivery. These cases highlight the benefits of fetal karyotype analysis and of an intact delivery and thorough clinical examination of the fetus when patients choose to terminate pregnancies with fetal anomalies.

Prenatal application of fluorescent in situ hybridization (FISH) for identification of a mosaic Y-chromosome marker, idic(Yp).

An amniocentesis was performed at 13.3 weeks' gestation for advanced maternal age. A mosaic sex chromosome pattern was found: of 50 cells examined, 34 had a 45,X karyotype. In 14 cells with a modal number of 46, a recognizable Y was substituted by a small non-fluorescent marker. C-banding identified the marker as an isodicentric in 12 cells. In two cells, the non-fluorescent marker appeared to be monocentric and looked like a non-fluorescent del (Yq), but could have been an isodicentric Y with inactivation of one of the centromeres. Two cells with a modal number of 47 showed two copies of the monocentric marker. Fluorescent in situ hybridization with an alpha satellite Y-specific centromeric probe confirmed the Y-chromosome origin of the markers and allowed for more accurate prenatal diagnostic information.

The need for developing standardized family pedigree nomenclature.

To assess the variation in usage of symbols used in recording a genetic family history, full members of the National Society of Genetic Counselors were surveyed by questionnaire. The questionnaire return rate was 55.3% and genetic counselors from a broad range of clinical experience, genetic counseling training programs and geographic regions responded. There was striking variation in symbols used for recording routine medical information in a genetic family history (i.e., pregnancy, spontaneous abortion, termination of pregnancy). There was even less consensus in recording situations representing new reproductive technologies (i.e., artificial insemination by donor semen, donor ovum, surrogate motherhood). The results of this survey document the need for developing standardized nomenclature in recording genetic family histories as a quality assurance measure in the delivery of genetic services. Such standardization will reduce the chance of incorrect interpretation of patient and family medical and genetic information.

Recommendations for standardized human pedigree nomenclature. Pedigree Standardization Task Force of the National Society of Genetic Counselors.

The construction of an accurate family pedigree is a fundamental component of a clinical genetic evaluation and of human genetic research. Previous surveys of genetic counselors and human genetic publications have demonstrated significant inconsistencies in the usage of common pedigree symbols representing situations such as pregnancy, termination of pregnancy, miscarriage, and adoption, as well as less common scenarios such as pregnancies conceived through assisted reproductive technologies. The Pedigree Standardization Task Force (PSTF) was organized through the Professional Issues Committee of the National Society of Genetic Counselors, to establish recommendations for universal standards in human pedigree nomenclature. Nomenclature was chosen based on current usage, consistency among symbols, computer compatibility, and the adaptability of symbols to reflect the rapid technical advances in human genetics. Preliminary recommendations were presented for review at three national meetings of human genetic professionals and sent to > 100 human genetic professionals for review. On the basis of this review process, the recommendations of the PSTF for standardized human pedigree nomenclature are presented here. By incorporating these recommendations into medical genetics professional training programs, board examinations, genetic publications, and pedigree software, the adoption of uniform pedigree nomenclature can begin. Usage of standardized pedigree nomenclature will reduce the chances for incorrect interpretation of patient and family medical and genetic information. It may also improve the quality of patient care provided by genetic professionals and facilitate communication between researchers involved with genetic family studies.

Recommendations for standardized human pedigree nomenclature.

The construction of an accurate family pedigree is a fundamental component of a clinical genetic evaluation and of human genetic research. Previous surveys of genetic counselors and human genetic publications have demonstrated significant inconsistencies in the usage of common pedigree symbols representing situations such as pregnancy, termination of pregnancy, miscarriage, and adoption, as well as less common scenarios such as pregnancies conceived through assisted reproductive technologies. The Pedigree Standardization Task Force (PSTF) was organized through the Professional Issues Committee of the National Society of Genetic Counselors, to establish recommendations for universal standards in human pedigree nomenclature. Nomenclature was chosen based on current usage, consistency among symbols, computer compatibility, and the adaptability of symbols to reflect the rapid technical advances in human genetics. Preliminary recommendations were presented for review at three national meetings of human genetic professionals and sent to >100 human genetic professionals for review. On the basis of this review process, the recommendations of the PSTF for standardized human pedigree nomenclature are presented here. By incorporating these recommendations into medical genetics professional training programs, board examinations, genetic publications, and pedigree software, the adoption of uniform pedigree nomenclature can begin. Usage of standardized pedigree nomenclature will reduce the chances for incorrect interpretation of patient and family medical and genetic information. It may also improve the quality of patient care provided by genetic professionals and facilitate communication between researchers involved with genetic family studies.