The adaptation of parents to a disabled infant was studied in relation to the type of disability presented by the baby. Participants were divided according to three types of disability and one control group: patents of infants with (1) Down's syndrome (DS), (2) congenital heart disease (CHD), (3) a cleft lip and/or palate (CLP), and (4) no disability (ND). The data were collected using a self-administered questionnaire given to each parent 6 months after the birth of their baby. The measures included parenting stress, stress appraisal, and psychological distress. Overall, the results indicate that parents of infants with DS and parents of infants with CHD report greater levels of parenting stress and psychological distress than parents of babies with CLP or non-disabled infants. Mothers were found to report greater levels of stress and distress overall, but differences across diagnostic groups were similar for mothers and fathers. The implications of the findings for theory and clinical intervention are discussed.

No abstract

The canine transmissible venereal tumor (CTVT) is a cancer lineage that arose several millennia ago and survives by “metastasizing” between hosts through cell transfer. The somatic mutations in this cancer record its phylogeography and evolutionary history. We constructed a time-resolved phylogeny from 546 CTVT exomes and describe the lineage’s worldwide expansion. Examining variation in mutational exposure, we identify a highly context-specific mutational process that operated early in the cancer’s evolution but subsequently vanished, correlate ultraviolet-light mutagenesis with tumor latitude, and describe tumors with heritable hyperactivity of an endogenous mutational process. CTVT displays little evidence of ongoing positive selection, and negative selection is detectable only in essential genes. We illustrate how long-lived clonal organisms capture changing mutagenic environments, and reveal that neutral genetic drift is the dominant feature of long-term cancer evolution.