Erroneous prenatal diagnosis of congenital adrenal hyperplasia owing to a duplication of the CYP21A2 gene.

Congenital adrenal hyperplasia (CAH) is an autosomal recessive disorder where steroidogenesis in the adrenal cortex is impaired. The most common form is caused by 21-hydroxylase deficiency (21OHD). Classical 21OHD is characterized by glucocorticoid and mineralocorticoid deficiency and by overproduction of adrenal androgens. The diagnosis rests on biochemical and genetic analyses. In families with history of CAH, prenatal genetic diagnosis is offered. We herein present a case of an infant whose parents were identified to carry mutations on the CYP21A2 gene. The fetal DNA analysis demonstrated that the fetus carried a paternal exon 8 (Q318X) mutation and a maternal exon 8 (R356X) mutation. The fetus was presumed to be affected with CAH, yet his clinical presentation at birth was not consistent with the diagnosis. Repeated genetic analysis identified a paternal CYP21A2 gene duplication with Q318X mutation on one copy of CYP21A2. We conclude that a duplication of the CYP21A2 gene should be suspected when clinical and hormonal findings do not support the genetic diagnosis. Furthermore, because individuals with Q318X mutation frequently have a duplication of the CYP21A2 gene, when Q318X is detected, it is important to distinguish the severe point mutation in single gene copy alleles from the non-deficient variant in gene-duplicated alleles.

Temporal lobe volume determined by magnetic resonance imaging in schizotypal personality disorder and schizophrenia.

The volumes of the whole temporal lobe, the superior temporal gyrus and the corpus callosum were measured on magnetic resonance images from 13 patients with schizotypal personality disorder (SPD), 27 patients with schizophrenia, and 31 age- and sex-matched controls. Temporal lobe structures were traced on consecutive 1.2mm thick SPGR images. Both patient groups had smaller temporal lobes than normal volunteers, a difference that was more marked for the area outside the superior temporal gyrus than for the STG. Correcting for brain volume diminished differences between normal subjects and schizophrenia patients, but the differences between normal subjects and SPD patients remained. Normal volunteers and SPD patients showed significant correlations between the sagittal section area of the posterior portion of the corpus callosum, which carries temporal interhemispheric connections, and the white matter volume of the temporal lobe. While the sample size is modest, taken together, these results suggest that the psychopathological symptoms of SPD may be related to temporal gray matter loss with relatively intact white matter connectivity, while the cognitive and psychotic symptoms of schizophrenia may be related to temporal gray loss combined with disruption of normal patterns of white matter development.