Prenatal chromosomal microarray analysis: a survey of prenatal genetic counselors' experiences and attitudes.

OBJECTIVE: Studies showing the efficacy and accuracy of chromosomal microarray analysis (CMA) in prenatal diagnosis may position it as a first-tier prenatal test. This study seeks to characterize the practices and attitudes of North American prenatal genetic counselors regarding CMA. METHOD: Genetic counselors (N = 196) in Canada and the USA responded to an anonymous online survey. Completed surveys were analyzed (n = 160). RESULTS: Most respondents viewed CMA as useful (73%), presented CMA to patients (84%), and had ordered CMA at least once (69%). The use of full versus targeted arrays varied. Logistic regression analyses identified three significant predictors for the view that prenatal CMA is useful: more prenatal counseling experience, younger age, and previously presenting CMA to a patient. Three factors predicted the likelihood of offering CMA to prenatal patients: percentage of time spent in prenatal practice, belief that CMA is useful, and practicing in the USA (versus Canada). Reasons cited for not using CMA included financial concerns, the possibility of ambiguous results, and ethical concerns. Most respondents (n = 111) believed that ambiguous results are an ethical issue. CONCLUSION: Clinical guidelines for prenatal CMA, further research on specific copy number variants, and broader availability of targeted arrays to reduce ambiguous results are needed.

Effect of maternal cystic fibrosis genotype on diabetes in pregnancy.

OBJECTIVE: To evaluate the association between the cystic fibrosis (CF) genotype and the rate of diabetes complicating pregnancy. METHODS: We conducted a retrospective cohort analysis of all pregnant patients with CF from 1972-2011 at a single institution. Patients who were homozygous for the ΔF508 mutation were compared with patients who were heterozygous for the ΔF508 mutation. Primary outcomes measured were incidence of CF-related diabetes and gestational diabetes mellitus (GDM) stratified by CF genotype. Secondary outcomes measured included pancreatic insufficiency, preterm premature rupture of membranes, preterm delivery, mode of delivery, gestational age at delivery, and maternal mortality. RESULTS: We identified 54 pregnancies among 36 women who met inclusion criteria. Of these pregnancies, 28 (51.9%) were carried by women who were homozygous for the ΔF508 mutation. Homozygous women had a significantly greater incidence of pancreatic insufficiency (89.3% compared with 61.5%, P=.03) and diabetes complicating pregnancy (60.7% compared with 23.1%, P<.01) compared with heterozygous women. In addition, there was some evidence of an increased incidence of GDM specifically among homozygous women (35.7% compared with 15.4%, P=.12). Regarding neonatal outcome, there was a lower mean birthweight (2,881 g compared with 3,203 g, P=.04) among the women who were homozygous for the ΔF508 mutation. There was no statistical difference in preterm deliveries, mode of delivery, gestational age at delivery, rate of preterm premature rupture of membranes, or incidence of maternal mortality between the two groups. CONCLUSION: Women with CF who are homozygous for the ΔF508 mutation have an increased risk of having a pregnancy complicated by diabetes.

22q11.2 deletion syndrome: attitudes towards disclosing the risk of psychiatric illness.

22q11.2 Deletion Syndrome (22q11.2DS) is a common microdeletion syndrome with multisystem features. There is a strong association with psychiatric disorders. One in every four to five patients develop schizophrenia. Despite studies showing that early diagnosis and treatment are likely to lead to improved outcome, genetic counselors may be reluctant to discuss the risk of psychiatric illness. The aim of this research was to explore parental attitudes and genetic counselors' perspectives and practice regarding disclosure of the clinical manifestations of 22q11.2DS, particularly the risk of psychiatric illness. We delivered a questionnaire to genetic counselors via established list-serves, 54 of which were completed. We also conducted interviews with four parents of adults with 22q11.2DS and schizophrenia. The majority of counselors and parents felt that the increased risk to develop a psychiatric illness is important to disclose. However, in the initial counseling session when the diagnosis was made in infancy genetic counselors were significantly less likely to discuss the risk of psychiatric disorders compared to other later onset features such as hypothyroidism (41 % vs. 83 %, p = 0.001). When the diagnosis of 22q11.2DS was made in infancy, counselors' responses in regard to timing of disclosure about psychiatric illnesses were fairly evenly divided between infancy, childhood and adolescence. In contrast, for other major features of 22q11.2DS, disclosure would predominantly be in infancy. The respondents reported that the discussion of psychiatric issues with parents was challenging due to the stigma associated with mental illness. Some also noted limited knowledge about psychiatric illness and treatment. These results suggest that genetic counselors could benefit from further education regarding psychiatric illness in 22q11.2DS and best strategies for discussing this important subject with parents and patients.