Coefficients of relationship by isonymy among the parents of Scottish twins: a test of familial aggregation

The ability of the coefficient of relationship by isonymy Ri to detect familial aggregation of conditions suspected of being under a degree of genetic control was tested on groups of fathers and mothers of like-sex twins, fathers and mothers of unlike-sex twins, and fathers and mothers of singleton controls born from 1977 to 1981 in Scotland. No statistically significant difference of within-group or between-group Ri was found, either for all surnames or for rare surnames only. However, the overall pattern of results for rare surnames showed a measure of agreement with what is already known of the genetics of twinning. The relatively high within-group Ri for mothers of unlike-sex twins is consistent with a maternal genetic influence on dizygous twinning, whereas the relatively high between-group Ri for fathers with mothers of unlike-sex twins suggests that paternal as well as maternal genes may be involved. Values of Ri for the parents of like-sex twins raise the possibility of a paternal but not a maternal genetic contribution to monozygous twinning.     

An approach to the assessment of change in the numbers of Canada Geese Branta canadensis and Greylag Geese Anser anser in southern Britain

Capsule Population change in geese was assessed using an approach that requires a relatively small sampling effort.

Aims During the 1999 breeding season a survey was carried out to determine if the numbers of introduced Canada and re-established Greylag Geese in southern Britain had changed since 1988–91 and whether any change had occurred in areas with previously high or low Canada Goose densities.

Methods A randomized stratified sample of 246 tetrads from the 24 156 tetrads covered between 1988–91 in this area, as part of the New Atlas of Breeding Birds, were resurveyed. Eight habitat categories were used in the stratification and were based on 1-km-square summary data obtained from the CEH Land Cover Map of Great Britain (water cover and urbanization) and LANDCLASS stratification (upland/lowland). The five habitat categories with the highest densities of Canada Geese and the greatest variance in numbers were sampled.

Results Between 1989 and 1999, the number of Canada Geese on land with over 5% water cover and on lowland with some water cover increased by on average 156%, an average rate of increase of 9.9% per annum. Southern Britain probably now holds a minimum of 82 000 Canada Geese. Between 1989 and 1999, the number of Greylag Geese on land with over 5% water cover and on lowland with some water cover increased by on average 214%, an average rate of increase of 12% per annum. Southern Britain probably now holds a minimum of 30 000 Greylag Geese.

Conclusion Maximum densities of Canada Geese may have been reached in high-density habitats but their numbers are still increasing very rapidly. Greylag Geese are increasing even more rapidly.     

Multiple changes in gene expression in chronic human Achilles tendinopathy.

Atlas cDNA cell interaction arrays (CLONTECH) were used to examine degenerate tissue from four patients with Achilles tendon disorders, in order to identify changes in expression of genes important in cell-cell and cell-matrix interactions. The greatest difference between normal (post-mortem) and degenerate tissue samples was in the level of MMP-3 (stromelysin) mRNA, which was down-regulated in all the degenerate samples. Quantitative RT-PCR assay of RNA extracted from paired 'normal' and degenerate Achilles tendon tissue samples taken from tendons during surgery mirrored the results of the arrays. Levels of MMP-3 mRNA were lower, whereas levels of type-I and type-III collagen mRNAs were significantly higher, in the degenerate compared to the 'normal' samples. Immunoblotting of proteins extracted from the same tendon samples showed that three of four normal tissue samples taken from individuals without apparent tendon disorder had much higher levels of MMP-3 protein than 'normal' or degenerate samples from patients with tendinosis. We suggest that MMP-3 may play an important role in the regulation of tendon extracellular matrix degradation and tissue remodelling.     

Nonanal in epicuticular wax of golden egg plums (Prunus domestica)

Nonanal was identified, as a major component, in the aldehyde fraction of the cuticular wax of the plum cultivar, Golden Egg. This compound was found to play an important role in the overall aroma of the plum.