Executive functions are amongst the most heritable cognitive traits with twin studies indicating a strong genetic origin. However genes associated with this domain are unknown. Our research into the neurodevelopmental disorder Williams-Beuren syndrome (WBS) has identified a gene within the causative recurrent 1.5/1.6 Mb heterozygous microdeletion on chromosome 7q11.23, which may be involved in executive functioning. Comparative genome array screening of 55 WBS patients revealed a larger ∼1.8 Mb microdeletion in 18% of cases, which results in the loss of an additional gene, the transcription factor GTF2IRD2. The GTF gene family of transcription factors (GTF2I, GTF2IRD1 and GTF2IRD2) are all highly expressed in the brain, and GTF2I and GTF2IRD1 are involved in the pathogenesis of the cognitive and behavioural phenotypes associated with WBS. A multi-level analysis of cognitive, behavioural and psychological functioning in WBS patients showed that those with slightly larger deletions encompassing GTF2IRD2 were significantly more cognitively impaired in the areas of spatial functioning, social reasoning, and cognitive flexibility (a form of executive functioning). They also displayed significantly more obsessions and externalizing behaviours, a likely manifestation of poor cognitive flexibility and executive dysfunction. We provide the first evidence for a role for GTF2IRD2 in higher-level (executive functioning) abilities and highlight the importance of integrating detailed molecular characterisation of patients with comprehensive neuropsychological profiling to uncover additional genotype-phenotype correlations. The identification of specific genes which contribute to executive function has important neuropsychological implications in the treatment of patients with conditions like WBS, and will allow further studies into their mechanism of action.

Cystic fibrosis (CF) is the most common recessive condition affecting the White British population. Facilitating reproductive decision making for couples at genetic risk for CF is an important aspect of genetic counseling practice in the UK. The purpose of this study was to explore the reproductive decision making process for 31 members of CF carrier couples (15 men and 16 women) with or without an affected child. The design involved a qualitative approach consisting of semi-structured interviews and data analysis informed by grounded theory methodology. Sex and personal experience of CF were identified as factors that may influence reproductive decision making. Findings suggest these hypotheses: (1) CF carrier couples who have an affected child/pregnancy, are more likely to embark on another pregnancy than couples who have a healthy child from an at-risk pregnancy, and (2) men and women play different roles in the reproductive decision making process. Data analysis resulted in development of a structured framework modeling the reproductive decision making process, which may be helpful in guiding genetic counseling with CF carrier couples and other at risk couples making reproductive decisions.