Age at first birth in women is genetically associated with increased risk of schizophrenia

Prof. Paunio on PGC:n jäsenPrevious studies have shown an increased risk for mental health problems in children born to both younger and older parents compared to children of average-aged parents. We previously used a novel design to reveal a latent mechanism of genetic association between schizophrenia and age at first birth in women (AFB). Here, we use independent data from the UK Biobank (N = 38,892) to replicate the finding of an association between predicted genetic risk of schizophrenia and AFB in women, and to estimate the genetic correlation between schizophrenia and AFB in women stratified into younger and older groups. We find evidence for an association between predicted genetic risk of schizophrenia and AFB in women (P-value = 1.12E-05), and we show genetic heterogeneity between younger and older AFB groups (P-value = 3.45E-03). The genetic correlation between schizophrenia and AFB in the younger AFB group is -0.16 (SE = 0.04) while that between schizophrenia and AFB in the older AFB group is 0.14 (SE = 0.08). Our results suggest that early, and perhaps also late, age at first birth in women is associated with increased genetic risk for schizophrenia in the UK Biobank sample. These findings contribute new insights into factors contributing to the complex bio-social risk architecture underpinning the association between parental age and offspring mental health.Peer reviewe

Leaf Chlorosis and Seed Yield of Dry Beans Grown on High-pH Calcareous Soil following Foliar Iron Sprays

Iron deficiency chlorosis (FeDC) causes extensive reduction in yields of edible dry beans (Phaseolus vulgaris L.) grown on high-pH and calcareous soils. Fifteen bean cultivars/lines differing in response to FeDC were grown 2 years (1988 and 1989) on a high-pH (8.0), calcareous (2.3% calcium carbonate equivalent in surface 20 cm), and low-Fe (2.2 mg Fe/kg) Typic Haplustolls silt loam in the field (central Nebraska) to determine the effects of FeDC on seed yield of cultivars/lines sprayed with Fe. A significant interaction (P \u3c 0.05) between cultivars/lines × Fe spray treatment was noted for visual FeDC ratings in 1988 only, and no significant interactions were noted for seed yield either year. Sprayed cultivars/lines generally produced higher yields than unsprayed ones. Overall increases were 47% in 1988 and 41% in 1989. Even though only slight FeDC was noted on some cultivars/lines receiving no Fe spray, seed yields were significantly increased when sprayed with Fe. Some cultivars/lines with moderate or moderately severe FeDC ratings did not show a significant increase in yield when sprayed with Fe, while other cultivars/lines did. Seed yield reductions for the cultivars/ lines per unit of FeDC rating (1 = green to 5 = severe chlorosis) were 915 kg·ha-1 for unsprayed and 1518 kg·ha-1 for sprayed plants in 1988 and 344 kg·ha-1 for unsprayed and 608 kg·ha-1 for sprayed plants in 1989