SEX-CHROMATIN AND SEX-CHROMOSOME ABNORMALITIES IN MALE HYPOGONADAL MENTAL PATIENTS

The Sex Chromosome Hypothesis of Schizophrenia: Alive, Dead, or Forgotten? A Commentary and Review

The X chromosome has long been an intriguing site for harboring genes that have importance in brain development and function. It has received the most attention for having specific genes underlying the X-linked inherited intellectual disabilities, but has also been associated with schizophrenia in a number of early studies. An X chromosome hypothesis for a genetic predisposition for schizophrenia initially came from the X chromosome anomaly population data showing an excess of schizophrenia in Klinefelter's (XXY) males and triple X (XXX) females. Crow and colleagues later expanded the X chromosome hypothesis to include the possibility of a locus on the Y chromosome and, specifically, genes on X that escaped inactivation and are X-Y homologous loci. Some new information about possible risk loci on these chromosomes has come from the current large genetic consortia genome-wide association studies, suggesting that perhaps this hypothesis needs to be revisited for some schizophrenias. The following commentary reviews the early and more recent literature supporting or refuting this dormant hypothesis and emphasizes the possible candidate genes still of interest that could be explored in further studies.

MRI and SPECT of Klinefelter's syndrome with various neuropsychiatric symptoms: a case report

We present here magnetic resonance imaging (MRI) and single photon emission computed tomography with 123I-N-isopropyl-p-iodoamphetamine (123I-IMP-SPECT) of a patient suffering from Klinefelter's syndrome with various neuropsychiatric symptoms. He was a 30-year-old male, who showed impaired consciousness seizures, auditory hallucination, delusion of reference, delusion of grandeur, psychomotor excitement and intellectual impairment. Although no focal lesion was detected by computed tomography or T1-weighted MRI, T2-weighted MRI provided a heterogeneous high-signal-intensity lesion of the inferior part of the left temporal lobe, which was not enhanced with Gd-DTPA. In addition 123I-IMP-SPECT exhibited focal hypoperfusion in the left temporal lobe on the early images. We suggest that the neuropsychiatric symptoms of this case are associated with the focal organic brain dysfunction which was revealed by MRI and 123I-IMP-SPECT.

Neuropsychiatric and experiential correlates of violent juvenile delinquency

This article reviews evidence regarding contributions of neuropsychiatric and psychological vulnerabilities to violent delinquency, and the interaction between intrinsic vulnerabilities and experiential factors in the genesis of antisocial juvenile behavior. Consideration is given to biochemical and physiological factors, genetics, medical status, and neurological, psychiatric, and neuropsychological factors. Implications for treatment are discussed.

Cytogenetic studies of males with schizophrenia. Screening for the fragile X chromosome and other chromosomal abnormalities

Genetic factors appear to play a role in the etiology of schizophrenia, although no specific genetic mechanism has yet been identified. As a preliminary measure in the search for the chromosomal location of a gene or genes relevant to this illness, cytogenetic screening of populations of patients might provide clues for further in depth molecular studies. Additionally, since the X chromosome has been implicated as a possible site, specific examinations aimed at identifying abnormalities in this chromosome including the presence of the fragile X site, could also be important. The following report reviews the previous literature on chromosomal aberrations in schizophrenia and presents data from a new survey of 46 unrelated male patients with schizophrenia. No chromosomal aberrations or folate-sensitive fragile sites were found in samples from these patients.

Sex chromatin and cytogenetic survey of 10417 adult males and 357 children institutionalized in Belgian institutions for mentally retarded patients

A survey of adult male immates of the major institutions for mental patients in Belgium was undertaken in 1965. Out of 10417 males examined 61 had positive sex chromatin (5.8%); 201 had bilateral small testis (1.9%), 4 hypogonad patients carried a D/D translocation. Out of 857 karyotyped children, 2.9% carried an autosomal or sex-chromosomal anomaly other than trisomy G. This prevalence of chromosomal anomalies in children with low I.Q. (less than 50) emphasizes the need for further studies.

Neuropsychiatric illness and neuropathological findings in a case of Klinefelter's syndrome

A case of Klinefelter's syndrome with XXY karyotype and a dementing neuropsychiatric illness associated with a diffuse degeneration of the deep cerebral white matter and adrenal cortical atrophy is presented. The possible relationships between genetic abnormalities and disordered function and structure of the brain are discussed in the light of the clinical and pathological observations.

A controlled study of the psychopathology and physical measurements of Klinefelter's syndrome

Klinefelter, Reifenstein and Albright (13) in 1942 collected and described nine cases of a new clinical syndrome, later given the eponym Klinefelter's Syndrome, which appeared at puberty in males and was characterized by gynaecomastia, hypogonadism, aspermatogenesis, increased follicle-stimulating hormone (F.S.H.) and normal or low 17-ketosteroid urinary excretion.

Neoplastic liability in Klinefelter's syndrome

One of the common clinical interests shared by physicians and psychiatrists is the genetically determined syndrome to which Klinefelter has given his name. Over the past few years positive identification has become possible through advances in cytogenetics, and more recently evidence has been accumulating which seems to indicate that a significant correlation may exist between Klinefelter's Syndrome and the development of other diseases, malignant disease in particular. Mental retardation is one of the most common symptoms found in the syndrome, so the psychiatrist is often in the best position to detect it. The case to be described here as well as having a few interesting facets of psychopathology may also provide more evidence of the pathological loading which the basic genetic abnormality seems to carry.