Integration of microarray technology into prenatal diagnosis: counselling issues generated during the NICHD clinical trial.

Cytogenetic microarray analysis (CMA) in prenatal testing detects chromosome abnormalities and new genetic syndromes that would be missed by conventional cytogenetics and has the potential to significantly enhance prenatal genetic evaluation. A large Eunice Kennedy Shriver National Institute Of Child Health and Human Development (NICHD)-sponsored multicentered trial to assess the role of CMA as a primary prenatal diagnostic tool has been completed, and results will soon be available. Integration of this technology into clinical care will require thoughtful changes in patient counseling. Here, we examine four cases, all ascertained in the NICHD prenatal microarray study, to illustrate the challenges and subtleties of genetic counseling required with prenatal CMA testing. Although the specifics of each case are distinct, the underlying genetic principles of uncertainty, variable expressivity, and lack of precise genotype-phenotype correlation are well known and already part of prenatal counseling. Counselor and practitioner education will need to include both the science of interpreting array findings as well as development of improved approaches to uncertainty. A team approach to interpretation will need to be developed, as will standardized guidelines by professional organizations and laboratories. Of equal import is additional research into patient attitudes and desires, and a better understanding of the full phenotypic spectrum of copy number variants discovered in utero.

High-Resolution genomic arrays identify CNVs that phenocopy the chromosome 22q11.2 deletion syndrome.

The 22q11 Deletion Syndrome includes the overlapping phenotypes of DiGeorge/Velocardiofacial Syndromes, characterized by conotruncal heart defects, cleft palate, thymus, and parathyroid gland dysplasia. The majority (90%) of patients harbor detectable chr22q11.2 deletions, but a genetic etiology for the remainder of patients without a deletion can remain undefined despite major birth defects. We analyzed DNA from eight patients with normal 22q11 FISH studies by high-density single nucleotide polymorphism (SNP) arrays and identified potentially pathogenic copy number variants (CNVs) in four of eight patients. Two patients showed large CNVs in regions of known genomic disorders: one a deletion of distal chr22q11.2 and the other a duplication of chr5q35. A 3-Mb deletion of chr19p13.3 that includes a gene associated with conotruncal heart defects was found in a third patient. Two potentially pathogenic CNVs were found in a fourth patient: a large heterozygous deletion of chr6p24 and a smaller duplication of chr9p24. Our findings support a recent consensus statement advocating chromosomal microarray analysis as a first-line diagnostic approach for patients with multiple congenital anomalies. In patients with phenotypes suggestive of the 22q11.2 syndrome spectrum and normal FISH, microarray analysis can uncover the molecular basis of other genomic disorders whose features overlap those of 22q11.2 deletions.

Physicians' communication of Down syndrome screening test results: the influence of physician numeracy.

PURPOSE: We investigated three questions: (1) How do obstetrician-gynecologists communicate positive and negative test results? (2) When reporting screening test results, do obstetrician-gynecologists use quantitative or qualitative information? and (3) Is physician numeracy (i.e., the ability to use and understand numbers) associated with use of quantitative or qualitative information? METHOD: Obstetrician-gynecologists (N = 203; 55.6% response rate) who were members of the American College of Obstetricians and Gynecologists completed a survey about their communication of Down syndrome screening test results, an Objective Numeracy Scale, and the Subjective Numeracy Scale. RESULTS: Higher scores on the Subjective Numeracy Scale and younger age predicted obstetrician-gynecologists' use of numbers to explain testing results. The Objective Numeracy Scale did not predict use of numbers. Gender was correlated with scores on the Subjective Numeracy Scale (r = 0.2) and the Subjective Numeracy Scale-Ability Subscale (r = 0.3), with men scoring higher than women when controlling for age. Open-ended questions revealed that communication strategies vary, with approximately one in three obstetrician-gynecologists providing numerical information, and frequency format being the commonly used numerical format. CONCLUSION: Although physicians are often overlooked in the problem of low health literacy, it is important that we continue to investigate the impact of physician numeracy on patient care.

Explaining the Black-White Disparity in Preterm Birth: A Consensus Statement From a Multi-Disciplinary Scientific Work Group Convened by the March of Dimes.

In 2017-2019, the March of Dimes convened a workgroup with biomedical, clinical, and epidemiologic expertise to review knowledge of the causes of the persistent Black-White disparity in preterm birth (PTB). Multiple databases were searched to identify hypothesized causes examined in peer-reviewed literature, 33 hypothesized causes were reviewed for whether they plausibly affect PTB and either occur more/less frequently and/or have a larger/smaller effect size among Black women vs. White women. While definitive proof is lacking for most potential causes, most are biologically plausible. No single downstream or midstream factor explains the disparity or its social patterning, however, many likely play limited roles, e.g., while genetic factors likely contribute to PTB, they explain at most a small fraction of the disparity. Research links most hypothesized midstream causes, including socioeconomic factors and stress, with the disparity through their influence on the hypothesized downstream factors. Socioeconomic factors alone cannot explain the disparity's social patterning. Chronic stress could affect PTB through neuroendocrine and immune mechanisms leading to inflammation and immune dysfunction, stress could alter a woman's microbiota, immune response to infection, chronic disease risks, and behaviors, and trigger epigenetic changes influencing PTB risk. As an upstream factor, racism in multiple forms has repeatedly been linked with the plausible midstream/downstream factors, including socioeconomic disadvantage, stress, and toxic exposures. Racism is the only factor identified that directly or indirectly could explain the racial disparities in the plausible midstream/downstream causes and the observed social patterning. Historical and contemporary systemic racism can explain the racial disparities in socioeconomic opportunities that differentially expose African Americans to lifelong financial stress and associated health-harming conditions. Segregation places Black women in stressful surroundings and exposes them to environmental hazards. Race-based discriminatory treatment is a pervasive stressor for Black women of all socioeconomic levels, considering both incidents and the constant vigilance needed to prepare oneself for potential incidents. Racism is a highly plausible, major upstream contributor to the Black-White disparity in PTB through multiple pathways and biological mechanisms. While much is unknown, existing knowledge and core values (equity, justice) support addressing racism in efforts to eliminate the racial disparity in PTB.

Pregnancy with Friedreich ataxia: a retrospective review of medical risks and psychosocial implications.

OBJECTIVE: Friedreich ataxia (FRDA) is an autosomal recessive, neurodegenerative disease. Recent medical advances have improved the average life expectancy, and as such, many female patients are contemplating pregnancy. However, little research exists exploring the medical or psychosocial complications that arise from pregnancy with this disease. STUDY DESIGN: In this study, we retrospectively examined 31 women with FRDA who had 65 pregnancies, resulting in 56 live offspring. RESULTS: FRDA did not appear to increase the risk of spontaneous abortion, preeclampsia, or preterm birth. Despite the sensory and proprioceptive loss that occurs in FRDA, nearly four fifths of births were vaginal. Of babies, 94.4% were discharged home with their mothers. Equal numbers of women reported that pregnancy made their disease symptoms worse, better, or unchanged. CONCLUSION: This study demonstrates that women with FRDA can have uncomplicated pregnancies that do not uniformly complicate disease symptomatology.

National Institutes of Health State-of-the-Science Conference Statement: Family History and Improving Health.

National Institutes of Health consensus and state-of-the science statements are prepared by independent panels of health professionals and public representatives on the basis of 1) the results of a systematic literature review prepared under contract with the Agency for Healthcare Research and Quality (AHRQ); 2) presentations by investigators working in areas relevant to the conference questions during a 2-day public session; 3) questions and statements from conference attendees during open discussion periods that are part of the public session; and 4) closed deliberations by the panel during the remainder of the second day and morning of the third. This statement is an independent report of the panel and is not a policy statement of the National Institutes of Health or the U.S. government. The statement reflects the panel's assessment of medical knowledge available at the time the statement was written. Thus, it provides a "snapshot in time" of the state of knowledge on the conference topic. When reading the statement, keep in mind that new knowledge is inevitably accumulating through medical research.

Screening for fetal aneuploidy and neural tube defects.

Maternal serum screening for neural tube defects and fetal aneuploidy in the second trimester has been incorporated into obstetrical practice over the past two decades. Now, as a result of several multicenter trials, first trimester screening between 11 and 14 weeks has been shown to be an effective and reliable screening test for Down syndrome and trisomy 18. This policy updates the American College of Medical Genetics policy statement entitled Second Trimester Maternal Serum Screening for Fetal Open Neural Tube Defects and Aneuploidy (2004), incorporates First trimester diagnosis and screening for fetal aneuploidy (2008) and complements the sections of American College of Medical Genetic's Standards and Guidelines for Clinical Genetics Laboratories entitled Prenatal Screening for Down syndrome (2005) and Prenatal Screening for Open Neural Tube Defects (2005).

Screening for Down syndrome: changing practice of obstetricians.

OBJECTIVE: We sought to assess the impact of American College of Obstetrician and Gynecologists (ACOG) guidelines on the practices and knowledge of obstetricians regarding screening for Down syndrome 1 year later. STUDY DESIGN: A questionnaire on Down syndrome screening was mailed to 968 ACOG Fellows and Junior Fellows. RESULTS: The response rate was 53%. The majority (95%) of respondents offer Down syndrome screening to all pregnant patients; 70% of general obstetricians offer the first-trimester screen and 86% the quad screen. Almost two-thirds (63%) of respondents are offering patients >/= 1 combination of first- and second-trimester screening tests. For women aged < 35 years, 70% offer amniocentesis selectively and 15% routinely. Chorionic villus sampling is offered less frequently. Respondents who more closely read the bulletin were more likely to say their practice had changed, answered more knowledge questions correctly, and felt more qualified to counsel patients. Most (85%) obstetricians personally counsel patients about Down syndrome risk and screening tests. The majority (94-95%) of respondents have access to adequate resources for screening within a 90-minute drive. CONCLUSION: Obstetricians have adopted a new paradigm for Down syndrome screening. First-trimester screening has been incorporated into prenatal care. Experience with these current screening tests will likely influence future guidelines and challenge the long-standing tradition of offering diagnostic testing based on maternal age. This study highlights the need for concise, unambiguous guidelines and a need to address unresolved issues in Down syndrome screening.

Evaluation of potential modifiers of the cardiac phenotype in the 22q11.2 deletion syndrome.

BACKGROUND: The phenotype associated with deletion of the 22q11.2 chromosomal region is highly variable, yet little is known about the source of this variability. Cardiovascular anomalies, including tetralogy of Fallot, truncus arteriosus, interrupted aortic arch type B, perimembranous ventricular septal defects, and aortic arch anomalies, occur in approximately 75% of individuals with a 22q11.2 deletion. METHODS: Data from 343 subjects enrolled in a study of the 22q11.2 deletion syndrome were used to evaluate potential modifiers of the cardiac phenotype in this disorder. Subjects with and without cardiac malformations, and subjects with and without aortic arch anomalies were compared with respect to sex and race. In addition, in the subset of subjects from whom a DNA sample was available, genotypes for variants of four genes that are involved in the folate-homocysteine metabolic pathway and that have been implicated as risk factors for other birth defects were compared. Five variants in four genes were genotyped by heteroduplex or restriction digest assays. The chi-square or Fisher's exact test was used to evaluate the association between the cardiac phenotype and each potential modifier. RESULTS: The cardiac phenotype observed in individuals with a 22q11.2 deletion was not significantly associated with either sex or race. The genetic variants that were evaluated also did not appear to be associated with the cardiovascular phenotype. CONCLUSIONS: Variation in the cardiac phenotype observed between individuals with a 22q11.2 deletion does not appear to be related to sex, race, or five sequence variants in four folate-related genes that are located outside of the 22q11.2 region.

First trimester diagnosis and screening for fetal aneuploidy.

Maternal serum screening for neural tube defects and fetal aneuploidy in the second trimester has been incorporated into obstetrical practice over the past two decades. Now, as a result of several multicenter trials, first trimester screening between 11 and 14 weeks has been shown to be an effective and reliable screening test for Down syndrome and trisomy 18. Benefits of first trimester screening include earlier identification of the pregnancy at risk for fetal aneuploidy and anatomic defects, in particular, cardiac anomalies, and the option of earlier diagnosis by chorionic villus sampling, if available. This policy updates the American College of Medical Genetics policy statement entitled Second Trimester Maternal Serum Screening for Fetal Open Neural Tube Defects and Aneuploidy (2004) and complements the sections of American College of Medical Genetic's Standards and Guidelines for Clinical Genetics Laboratories entitled "Prenatal screening for Down syndrome that includes first trimester biochemistry and/or ultrasound measurements."

Molecular and genetic aspects of DiGeorge/velocardiofacial syndrome.

Cytogenetic, molecular, and clinical genetic studies have contributed to our understanding of the etiology, pathogenesis, and natural history of DiGeorge syndrome (DGS) and velocardiofacial syndrome (VCFS). Submicroscopic deletions of chromosome 22ql 1.2 are the leading cause of both of these disorders. The 22q 11.2 deletion syndrome is recognized as one of the most common microdeletion syndromes. The clini'cal features are highly variable and include a variety of congenital anomalies, medical problems, and cognitive and neuropsychological difficulties. Infrequently, other chromosomal rearrangements are found in patients with DGS/VCFS, and, rarely, point mutations in the gene TBX1, a transcription factor, that maps to the deleted region. The most sensitive and widely used diagnostic test for detecting the 22ql 1.2 deletion is fluorescence in situ hybridization using probes from the commonly deleted region. Alternatively, polymerase chain reaction can be performed to confirm failure to inherit a parental allele in the region or to determine copy number. Prenatal diagnosis is also available, particularly when a conotruncal cardiac defect is identified during a pregnancy or when a parent carries a deletion. Genetic counseling is recommended before testing to review the natural history of the disorder, testing options, and test sensitivity and limitations.

Impact of self-reported familiarity with guidelines for cystic fibrosis carrier screening.

OBJECTIVE: To assess the impact of self-reported familiarity with published guidelines on knowledge, implementation, and opinions of obstetrician-gynecologists regarding carrier screening for cystic fibrosis. METHODS: A questionnaire pertaining to cystic fibrosis screening guidelines was mailed to 1,165 members of the American College of Obstetricians and Gynecologists. RESULTS: Sixty-four percent of questionnaires were returned. Statistical analyses were limited to the 632 respondents whose primary medical specialty was gynecology (GynOnly) or obstetrics and gynecology (ObGyns). More ObGyns had thoroughly read or skimmed the guidelines (67.1%) than had GynOnlys (41.6%). Correctly responding to basic questions regarding cystic fibrosis was associated with having read the guidelines, although responding to a more complex question was not. Familiarity with the guidelines was associated with correctly identifying the recommendations for offering screening, with practice implementation of cystic fibrosis screening, and with self-ratings of qualifications and training to offer screening and to provide counseling. In contrast, familiarity with the guidelines was not associated with ObGyn's opinion that burden of disease is likely to be influential in patient acceptance of screening. Physicians who had thoroughly read the guidelines were more likely to disagree that the cystic fibrosis screening test is too inaccurate to risk influencing reproductive decision making (thoroughly read = 79% disagree, skimmed = 69%, not read = 58%, not heard of it = 50%). CONCLUSION: There was a strong association between self-reported familiarity with the American College of Obstetricians and Gynecologists/American College of Medical Genetics guidelines and physicians' knowledge, implementation, and ratings of training for offering cystic fibrosis carrier screening.

Omodysplasia: an affected mother and son.

We describe a second family with mother to son transmission of omodysplasia, a rare skeletal dysplasia characterized by shortened humeri, shortened first metacarpals and craniofacial dysmorphism. The mother in this family had been diagnosed previously with Robinow syndrome; subsequently, her diagnosis was reclassified. Her pregnancy was closely monitored antenatally with serial ultrasound examinations. Delayed ossification of the humerus was noted prenatally. Her son had ambiguous genitalia and similar skeletal manifestations as his mother. A comparison to other known and suspected cases of dominant omodysplasia is presented. Our observations confirm the existence of a dominant variant of omodysplasia, document genital hypoplasia as an important feature of this syndrome in males and highlight the need to differentiate this entity from Robinow syndrome.

Polycystic ovary syndrome in adolescence.

Polycystic ovary syndrome (PCOS) is a common disorder among reproductive-age women, yet the diagnosis may be overlooked during adolescence. Although the clinical and metabolic features are similar to those found in adult women, it can be difficult to distinguish the young woman with PCOS from a normal adolescent. Irregular menses, anovulatory cycles, and acne are not uncommon in adolescent women. Adolescents with a history of premature pubarche, a family history of PCOS, Caribbean-Hispanic and African-American ancestry, and/or obesity are at risk for PCOS and deserve close surveillance. The laboratory evaluation of the adolescent with suspected PCOS or hyperandrogenism should be individualized based on the history, symptoms, and examination findings. The cornerstone of management of PCOS in adolescence includes either a combination oral contraceptive or progestin. Consideration of insulin-sensitizing agents, antiandrogens, topical treatments for acne, and various treatments for hair removal are dependent on the patient's symptoms and concerns. Healthy eating, regular exercise, and for the overweight adolescent, weight reduction, are encouraged to reduce the risk of cardiovascular disease and type II diabetes mellitus. Numerous studies have shown that weight loss and exercise decrease androgen levels, improve insulin sensitivity, and lead to the resumption of ovulation. Although initial studies suggest that Metformin may be particularly useful for treating the PCOS adolescent with insulin resistance and obesity, additional studies are needed to determine the efficacy and long-term outcome. Management of the adolescent with PCOS is challenging and requires a supportive, multidisciplinary team approach for optimal results.

ACOG Technology Assessment in Obstetrics and Gynecology. Number 1, July 2002. Genetics and molecular diagnostic testing.

Knowledge of human genetics has increased dramatically in the past few decades. The genetic basis of disease and the response to therapy is rapidly being elucidated and may soon become a part of routine medical practice. This document reviews the basics of genetic transmission and genetic technologies in current use.

Polycystic ovary syndrome in adolescence.

Polycystic ovary syndrome (PCOS) is a relatively common disorder among adolescent women. The typical clinical features including menstrual irregularities and hirsutism are usually not apparent until middle to late adolescence. Yet studies suggest that PCOS may begin in early puberty. Young women with premature pubarche, a family history of PCOS, Caribbean Hispanic and African American ancestry, and/or obesity are more likely to develop PCOS. Adolescents with PCOS may have elevated total or free testosterone, androstenedione, and luteinizing hormone levels; insulin resistance; and hyperinsulinemia. The laboratory evaluation and management of the adolescent with suspected PCOS should be individualized on the basis of the clinical features and symptoms. The cornerstone of most treatment strategies includes either a combination oral contraceptive or progestin to decrease testosterone levels and regulate the menstrual cycle. Consideration of insulin-sensitizing agents, antiandrogens, topical treatments for acne and excess facial hair, and hair removal is dependent on the patient's symptoms and concerns. A healthy approach to eating, in some cases weight loss, and exercise is encouraged to reduce the risk of cardiovascular disease and type 2 diabetes mellitus. Management of the adolescent with PCOS is challenging and often requires a supportive, multidisciplinary team approach for optimal results.

Molecular basis of pubertal abnormalities.

The causes of abnormal pubertal development are numerous. Recent molecular investigation has increased our understanding of the genetic basis of pubertal disorders. Investigators have identified some of the genes that are critical for normal puberty and have begun to elucidate the genes and pathogenesis of genetic disorders associated with abnormal pubertal development. Identification of specific chromosomal abnormalities and gene mutations allows for diagnostic testing and enables the clinician to provide accurate counseling of the recurrence risk for relatives. In the future, knowledge of the genetic basis of these disorders will facilitate the development of novel therapies and approaches to the fertility assessment and treatment of individuals with pubertal disorders. Although great strides have been made in identifying these genes, questions remain. Why do some genetic mutations affect puberty differentially in males and females? What is the long-term impact in terms of future fertility, and what is the risk to the offspring of such patients? Further research is needed to address these issues and to identify additional genetic loci involved in pubertal development.