Childhood intelligence is heritable, highly polygenic and associated with FNBP1L.

Intelligence in childhood, as measured by psychometric cognitive tests, is a strong predictor of many important life outcomes, including educational attainment, income, health and lifespan. Results from twin, family and adoption studies are consistent with general intelligence being highly heritable and genetically stable throughout the life course. No robustly associated genetic loci or variants for childhood intelligence have been reported. Here, we report the first genome-wide association study (GWAS) on childhood intelligence (age range 6-18 years) from 17,989 individuals in six discovery and three replication samples. Although no individual single-nucleotide polymorphisms (SNPs) were detected with genome-wide significance, we show that the aggregate effects of common SNPs explain 22-46% of phenotypic variation in childhood intelligence in the three largest cohorts (P=3.9 × 10(-15), 0.014 and 0.028). FNBP1L, previously reported to be the most significantly associated gene for adult intelligence, was also significantly associated with childhood intelligence (P=0.003). Polygenic prediction analyses resulted in a significant correlation between predictor and outcome in all replication cohorts. The proportion of childhood intelligence explained by the predictor reached 1.2% (P=6 × 10(-5)), 3.5% (P=10(-3)) and 0.5% (P=6 × 10(-5)) in three independent validation cohorts. Given the sample sizes, these genetic prediction results are consistent with expectations if the genetic architecture of childhood intelligence is like that of body mass index or height. Our study provides molecular support for the heritability and polygenic nature of childhood intelligence. Larger sample sizes will be required to detect individual variants with genome-wide significance.

A prospective study of the effects of breastfeeding and FADS2 polymorphisms on cognition and hyperactivity/attention problems.

Breastfeeding has been associated with improved cognitive functioning. There is a beneficial effect on IQ, and possibly on associated phenotypes such as attention problems. It has been suggested that the effect on IQ is moderated by polymorphisms in the FADS2 gene, which is involved in fatty acid metabolism. In this study we tested the relation between breastfeeding and FADS2 polymorphisms on the one hand and IQ, educational attainment, overactivity, and attention problems on the other hand. IQ at age 5, 7, 10, 12, and/or 18 (n = 1,313), educational attainment at age 12 (n = 1,857), overactive behavior at age 3 (n = 2,560), and attention problems assessed at age 7, 10, and 12 years (n = 2,479, n = 2,423, n = 2,226) were predicted by breastfeeding and two SNPs in FADS2 (rs174575 and rs1535). Analyses were performed using structural equation modeling. After correction for maternal education, a main effect of breastfeeding was found for educational attainment at age 12 and overactive behavior at age 3. For IQ, the effect of breastfeeding across age was marginally significant (P = 0.05) and amounted to 1.6 points after correcting for maternal education. Neither a main effect of the FADS2 polymorphisms nor an interaction with breastfeeding was detected for any of the phenotypes. This developmentally informed study confirms that breastfeeding is associated with higher educational attainment at age 12, less overactive behavior at age 3 and a trend toward higher IQ after correction for maternal education. In general, the benefits of breastfeeding were small and did not interact with SNPs in FADS2.

Steerable catheter fluoroscopy in total esophageal obstruction.

We describe a patient with malignant esophageal obstruction in whom the lumen of the esophagus could not be identified at endoscopy. Contrast fluoroscopy using a steerable catheter allowed safe placement of a nasoduodenal feeding tube.

Benign, atraumatic, bronchoesophageal fistulae.

We report two patients with bronchoesophageal fistulae resulting from benign causes. The first resulted from erosion of an acquired middle esophageal diverticulum. The second had the prolonged clinical course of a presumed congenital fistula. The importance of barium examinations in evaluating chronic respiratory complaints is emphasized.

Torsion of a wandering spleen.

Splenic torsion is an uncommon cause of abdominal pain. It often leads to death and seldom has been diagnosed preoperatively. We report a patient in whom the anatomy of the lesion is illustrated, together with its predisposing factors and diagnostic features.

Pneumocolon as an aid to small-bowel studies.

A prospective study was performed in 138 consecutive patients referred for small-bowel examination to evaluate the use of the pneumocolon when there was poor demonstration of the terminal ileum. One hundred and twenty-two patients were examined by enteroclysis (small-bowel enema) and 16 by small-bowel meal. Pneumocolon was used in 38 of the small-bowel enemas and in eight of the small-bowel meal examinations. In 29 cases (21 small-bowel enema; eight small-bowel meal) the use of the pneumocolon significantly improved demonstration of the terminal ileum. When the distal ileum is not adequately seen on a small-bowel study, pneumocolon serves as a useful additional technique.

Interobserver variation in the interpretation of abdominal radiographs.

A total of 140 sets of abdominal radiographs were reviewed independently by four qualified diagnostic radiologists. The degree of interobserver agreement was determined by calculating kappa values for 19 commonly used radiographic signs and diagnoses. There was fair to excellent interobserver agreement for 11 signs and diagnoses and poor agreement for the remaining eight. The signs and diagnoses for which agreement is poor cannot be considered reliable and include particularly large bowel obstruction and nonspecific gas pattern.