Marriage does not relate to major histocompatibility complex: a genetic analysis based on 3691 couples

Optimization of chances for healthy offspring is thought to be one of the factors driving mate choice and compatibility of the major histocompatibility complex (MHC) is assumed to determine the offspring's fitness. While humans have been claimed to be able to perceive information of MHC compatibility via the olfactory channel, it remains unknown whether humans use such information for mate choice. By investigation of 3691 married couples, we observed that the high polymorphism of MHC leads to a low chance for homozygous offspring. MHC similarity between couples did not differ from chance, we hence observed no MHC effect in married couples. Hormonal contraception at the time of relationship initiation had no significant effect towards enhanced similarity. A low variety of alleles within a postcode area led to a higher likelihood of homozygous offspring. Based on this data, we conclude that there is no pattern of MHC dis-assortative mating in a genetically diverse Western society. We discuss the question of olfactory mate preference, in-group mating bias and the high polymorphism as potential explanations.

Uncomplicated Phacoemulsification and First-Day Review: The Patient's Perspective

Purpose To evaluate patients’ opinions regarding first-day review following uncomplicated phacoemulsification. Methods A prospective questionnaire-based survey was conducted on consecutive patients at the time of listing for day-case phacoemulsification. Data collected included demographic details, proposed anaesthetic technique, first or second eye surgery and postcode. Statistical analysis was undertaken with the unpaired t-test, the χ2-test with Yates’ correction for small numbers or Fisher's exact test, and Kendal's rank correlation, as appropriate. Results 100 patients (59% female; mean age 74.2 (12.6) years) were recruited. 87% preferred to return to hospital for their first-day review. This result was not significantly affected by sex, proposed anaesthetic technique, first eye surgery or postcode area. Only patients Conclusions In this population, patients preferred to return for first-day review following uncomplicated phacoemulsification. There may be some variance in the opinions of surgeons and patients regarding this issue, and the patient's preferences should be taken into account to provide optimum quality of care.

Use of drugs, alcohol and tobacco by people with schizophrenia: case–control study

BackgroundSpecialised services should be developed to help people with schizophrenia and associated substance misuse. The extent of the problem therefore needs to be known.AimsTo determine the use of drugs, alcohol and tobacco by people with schizophrenia drawn from rural, suburban and urban settings, and to compare use by general population control subjects.MethodPeople with schizophrenia (n=316) and general population controls of similar gender distribution, age and postcode area of residence (n=250) were identified in rural, urban and suburban areas of Scotland. Use of drugs and alcohol was assessed by the Schedules for Clinical Assessment in Neuropsychiatry, and use of tobacco by a questionnaire.ResultsMore patients than controls reported problem use of drugs in the past year (22 (7%) v. 5 (2%)) and at some time before then (50 (20%) v. 15 (6%)) and problem use of alcohol in the past year (42 (17%) v. 25 (10%)) but not at sometime previously (99 (40%) v. 84 (34%)). More patients were current smokers (162 (65%) v. 99(40%)).ConclusionsProblem use of drugs and alcohol by people with schizophrenia is greater than in the general population, but absolute numbers are small. Tobacco use is the greatest problem.

Premium Rating by Geographic Area Using Spatial Models

This paper gives a method for premium rating by postcode area. The method is based on spatial models in a Bayesian framework and uses the Gibbs sampler for estimation. A summary of the theory of Bayesian spatial methods is given and the data which was analysed by Taylor (1989) is reanalysed. An indication is given of the wide range of models within this class which would be suitable for insurance data. The aim of the paper is to introduce the models and to show how they can be utilised in an insurance setting.