Genetic counseling and neonatal screening for cystic fibrosis: an assessment of the communication process.

OBJECTIVE: To assess the effectiveness of communication between health care providers (physicians, nurses, genetic counselors) in Wisconsin and parents of children identified as heterozygote carriers for cystic fibrosis (CF) in the routine Wisconsin Newborn Screening Program that was implemented using trypsinogen/DNA testing. METHODS: Routine CF neonatal screening, implemented in July 1994, involved a statewide system that recommended but did not mandate follow-up sweat tests at 1 of the Wisconsin's 2 certified CF centers. The Wisconsin Division of Health sent requests to participate to the parents of 483 infants identified as CF carriers between July 1994 and December 1997. Of the 483 parents, 183 agreed to participate and were asked to complete a questionnaire assessing their CF newborn screening experiences and their knowledge of CF genetics and any changes they made in their reproductive behavior as a result of this knowledge. Follow-up telephone interviews by a genetic counselor were attempted within 1 year for those completing the questionnaire. RESULTS: Within 4 months after the mailing, 138 of 183 (75%) parents completed the questionnaire. Subsequently, 123 of the 138 responders (89%) were contacted and interviewed by telephone. We learned that 67.6% of parents recalled receiving genetic counseling, but 32.4% of parents apparently did not participate in a risk communication session. When asked, "Who performed the genetic counseling?" parents indicated that their communication was with physicians in 8% of cases, nurses in 12.4%, and certified genetic counselors in 32.8% of cases; 17.5% of parents did not recall who performed the genetic counseling and 29.2% of parents indicated they did not receive genetic counseling. Based on the 138 responses, it was found that 88.3% of parents understood that their child was a carrier for CF, but 15.4% of parents were unsure whether being a carrier could cause illness. In addition, 12.4% of parents were unsure whether at least 1 of them (parents) was a carrier of the CF gene. Only 57% of parents knew there was a 1 in 4 chance that their child could have a child with CF if he or she reproduced with another carrier of the CF gene. Statistically significant differences were noted when comparing the frequency of correct responses between parents who received genetic counseling and parents who had not. The frequency of accurate responses did not depend on which health care professional provided the genetic counseling. Comparing responses of parents who were seen at a certified CF center with parents seen at other community hospitals and clinics revealed significant differences in the frequency of correct responses, with the former group showing a higher percentage of correct responses. Telephone interviews revealed that 11.4% of parents were unaware that their child was a carrier for CF and that 54.5% wished they had more information made available to them at the time of the initial positive newborn screen result, before the definitive sweat test. Also, 13.8% of parents recommended that community physicians be better informed of the details and implications of positive screening results for CF. CONCLUSION: Genetic counseling is imperative for the success of newborn screening for CF and other congenital diseases. With the completion of the Human Genome Project, more molecular screening for childhood disease is bound to enter the clinical arena. Based on our findings, efforts must be made to ensure that newborn screening programs have the means and the methods to communicate newborn screening results effectively to families. In addition, both the general public and community health providers must be better informed of the implications of all newborn screening results. Additional research is needed to determine whether there are communication styles and approaches that are better suited to counseling parents regarding newborn screening results.

A practical approach to familial and hereditary colorectal cancer.

Recent genetic research has isolated the primary genetic defect underlying many of the hereditary colorectal cancer syndromes. Obtaining a detailed family history is the first step in identifying individuals at increased risk of developing colorectal cancer. Once identified, individuals and their families may benefit from earlier, more intensified surveillance, prophylactic surgery, cancer risk assessment and education, and genetic testing. Clinicians, especially those with many patients with colorectal cancer in their practice, must be able to address the complex issues associated with the familial and hereditary colorectal cancer syndromes. A well-integrated partnership among colorectal surgeons, gastroenterologists, oncologists, and medical geneticists is necessary to address these complex issues and provide comprehensive medical care.

Deletion of 1q in a patient with acrofacial dysostosis.

The Nager syndrome is the most common form of acrofacial dysostosis. Although autosomal dominant and recessive forms of acrofacial dysostosis have been described the molecular etiology of these disorders is unknown. We report on a child with acrofacial dysostosis, critical aortic stenosis, and a deletion of chromosome 1q involving the heterochromatic block and adjacent euchromatin.

Unique cardiac and cerebral anomalies with chondrodysplasia punctata.

Chondrodysplasia punctata (CDP) is associated with a variety of genetic and nongenetic conditions. We report a girl with CDP, complex congenital cardiac disease, central nervous system (CNS) anomalies, and clinical findings that resemble those of the sibs described by Toriello et al. [1993, Am J Med Genet 47:797-799]. The cardiac defects and CNS abnormalities reported are unique in the context of CDP and may serve to expand the phenotypic spectrum of the unique form of CDP described by Toriello et al. [1993].

Segregation analysis of breast cancer: a comparison of type-dependent age-at-onset versus type-dependent susceptibility models.

Most segregation analyses of breast cancer susceptibility have modeled the effect of the major gene on the age-at-onset distribution. However, in families linked to BRCA1 or BRCA2, there is wide variation in the age-at-onset among gene carriers. We performed a segregation analysis of 544 Minnesota breast cancer families using models which parameterized the putative major gene effect in two ways: earlier age-at-onset, with a common level of susceptibility (model I), and greater susceptibility, with a common mean age-at-onset (model II). Five hypothetical modes of transmission and an unrestricted general hypothesis were fitted to the data. Twice the difference between the log(e) likelihood for the data under the specified hypothesis (recessive, no major gene, etc.) and the log(e) likelihood under the general hypothesis is distributed asymptotically as a chi-square statistic with the degrees of freedom equal to the difference in the number of parameters estimated. This difference was compared to the critical value for the chi-square distribution to assess goodness-of-fit. Under model I, both Mendelian and non-Mendelian hypotheses were rejected. When model II was used, the non-Mendelian hypotheses were rejected whereas all Mendelian hypotheses were not. Mendelian recessive inheritance of a common allele (qA = 0.11) with a high penetrance (87%) provided the best fit to the data. We then stratified the families into two subsets based on the age at diagnosis of the proband [< or = 55 years (n = 265) versus > 55 years (n = 279)]; there was no evidence of heterogeneity under either model (I or II). These data suggest that, in some breast cancer families, the effect of the putative susceptibility gene is better represented as increasing overall susceptibility to breast cancer rather than as a shift in the age-at-onset distribution.