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Previous studies of XXY boys suggest that they are at risk for certain communication disorders involving oral and written language. In this study, the language, reading, and spelling skills of a group of 14 XXY boys identified during neonatal cytogenetic screening were compared with those of a group of 15 control children. The two groups were matched for age, grade, race, parity, birth weight, parental age and education, and socioeconomic status. The mean age of the XXY group was 9 years 7 months and that of the control group was 9 years 3 months. The mean academic grade level for both groups was at the transition between third and fourth grade. There was selective reduction in verbal IQ scores for the XXY group and no significant differences apparent between groups for performance IQ scores. The decrease in verbal IQ was associated with a reduced full-scale IQ and also with significant problems in expressive language, auditory processing abilities, and auditory memory. Word-finding difficulties and problems in the production of syntax were major components of the specific expressive language deficit. Except for difficulties in the understanding of complex sentence structures, the receptive language skills of XXY boys did not differ significantly from those of the control group. These reductions in speech and language abilities correlated with decreased achievement by the XXY group on a variety of reading and spelling tasks. These results suggest that difficulty learning how to read and spell may be due to a preexistent language disability. Early attention to such expressive language problems may be essential to ameliorate secondary maladaptive behaviors due to chronic language-related learning disabilities.

Recent advances in the biological sciences have offered new opportunities to identify biological contributions as they interact with social experience to help determine psychological development. The role of biological factors is more easily demonstrated in subhuman species in which extensive experimental manipulations of variables are possible. One strategy for the study of human behaviour genetics has been the systematic analysis of behaviour in individuals with naturally occurring X chromosome variations. The aim has been to demonstrate whether or not the range of expected variability in particular areas of behavioural development was narrowed by the specific genotypic abnormality. The knowledge obtained from these studies can be applied meaningfully to enhance our understanding about human behavioural development in chromosomally unaffected individuals.

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The epidemiological data pertaining to the XYY genotype suggest that there is a three- to fourfold overrepresentation of XYY individuals in mental and penal settings and a twentyfold overrepresentation of mental-penal (special security) settings. The reasons behind the risk for behavioral disability are not known at this time. Tallness and ondulocystic acne are reported frequently to be associated with the genotype. Since much of the available information about the XYY sex chromosome complement is biased, more data is required before definitive statements can be made about the personality characteristics or intelligence of the vast majority of XYY men not appearing in social settings oriented towards behavioral deviancy.

A girl presented on the 9th day of life with familial lactic acidosis, euglycemia and hepatomegaly; death occurred at day 15. Ratios for plasma lactate: pyruvate (130:l) and B-hydroxybutyrate: acetoacetate (38:l) were elevated suggesting an imbalance of tissue NAD:NADH. Plasma pyruvate (0.?.5mM, Norm = <.07mM) and alanine (1.7mM, Norm = C.4rnl-l) were both elevated indicating a defect in pyruvate utilization. Organic acids other than those above were not elevated in urine. Skin fibroblasts produced excess lactic acid in culture. Evolution of 14-co2 (nmoleslmg prot hr f S.D.) from 1mM L-114~ lactate (control = 19.8 f 9.4), L-114~ pyruvate (control = 41.1 f 4.7) or L -~1 4~ alanine (control = 12.7 f 4.1) was markedly decreased compared to control cells (< lo%, C 1% and jj or JJ rats (p < .05). A correlation (rc.81) exists between BGT an& AD (p < .01) in JJ rats, but not in Jj rats. The data suggests a microsomal membrane defect in enzyme compartmentation may be the primary abnormality in the Gunn rat and possibly in Crigler-Najjar Syndrome. Of particular interest was the denonstration of mrd-finding difficulties and problem in the use of syntax as major factors in the expressive language deficit. Except for difficulties with syntax, receptive language skills were relatively normal. These results suggest that left-henisphere-based difficulty i n serial order processing may be associated with the XXY anmly, as ccmpared with right-hanisphere deficits in spatial processing that have been associated with XO Turner syndrane. Propionate is formed by the catabolism of isoleucine, valine, threonine and methionine, by the oxidation of odd-numbered carbon chain fatty acids and by the degradation of the t...