Vital records of Saybrook and Plymouth in New England from the 17th century were investigated. Among 8,562 maternities 81 twin maternities were found, the twinning rate being 0.95%. Twinning rate was low at the 1st and 2nd births as compared with the 3rd or later births, and was highest at the 7th and 8th births (1.6%). Twin maternity seemed to be a strong risk factor to terminate reproduction, pa
There has been long-standing interest in the effects of maternal age, birth rank, and birth spacing on infant and child mortality. Contradictory inferences about the role of these factors have arisen on occasion because of the absence of adequate controls, the use of cross-sectional or incomplete reproductive histories, and inattention to the effect of family size goals and birth limitation practi
The complete sequence of the 16,569-base pair human mitochondrial genome is presented. The genes for the 12S and 16S rRNAs, 22 tRNAs, cytochrome c oxidase subunits I, II and III, ATPase subunit 6, cytochrome b and eight other predicted protein coding genes have been located. The sequence shows extreme economy in that the genes have none or only a few noncoding bases between them, and in many cases the termination codons are not coded in the DNA but are created post-transcriptionally by polyadenylation of the mRNAs.
A transvascular endomyocardial biopsy from an infant with cardiomyopathy and chronic congestive heart failure showed abnormal mitochondria when examined by electron microscopy. At necropsy, similar abnormal mitochondria were seen in skeletal muscles, liver, and kidney. The patient’s family pedigree revealed several male babies who had cardiac disease and died in infancy. Myocardium obtained