Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0025362 (mental retardation)
 15,878 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

A child with terminal deletion of the long arm of the Y chromosome (Yq--) presented with marked livedo reticularis, snub nose, microcephaly, short stature, and other dysmorphic features. He was profoundly mentally retarded. Most of the patients with Yq- have been reported as having varying dysmorphic features, mental retardation, and short stature. This child, in addition to the above, has livedo reticularis and microcephaly. He was of normal birthweight and, therefore, does not come into the syndrome of microcephaly, snub nose, livedo reticularis, and low birthweight dwarfism. Further information on Yq- should be obtained to ascertain if consistent patterns of abnormalities exist.
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PMID:Yq- in a child with livedo reticularis, snub nose, microcephaly, and profound mental retardation. 714 92

A family is reported in which the mother and two sons are carriers of a Y-X translocation. The distal segment of the short arm of the X chromosome appears to have been deleted to give place to a translocation of the distal part of the long arm of the Y chromosome. Apart from short stature the mother is essentially free of stigmata, while the sons show a combination of mental retardation, hypertelorism, simian creases, clinodactyly, scanty palmar lines, and dry fragile skin. The cases described are discussed against the background of the few known previously published cases.
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PMID:Y-to-X chromosome translocation observed in two generations. 745 Jul 55

A 48 year old patient was hospitalised because of parasuicidal behaviour and suicidal ideation. He was under suspicion of having sexually abused his 4-year old daughter and his 4-year old son. At the age of 17, he was hospitalised in a psychiatric ward under the diagnosis of hebephrenic schizophrenia. He successfully received an insulin coma therapy. Because of his increased height (1.89 m), mental retardation and other psychical disorders in his youth, we now suspected him of having an extra Y chromosome which was confirmed by chromosome analysis. The non-uniform symptomatology of XYY-individuals includes a hebephrenic aspect. Concerning the different therapeutical and juridical consequences, we considered a critical investigation of the former diagnosis "Hebephrenic Schizophrenia".
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PMID:[Hebephrenic symptoms as an expression of an XYY chromosome abnormality? Case report of a patient with suspected sexual abuse of his own 2 minor children]. 763 85

A case, diagnosed as 18p-syndrome by typical clinical appearance and by chromosomal analysis, presented with multiple nervous system defects consisting of bilateral pyramidal tract signs, weakness and focal dystonia of the lower extremities, and concentric visual field defect. Chromosomal analysis revealed karyotype 46, X, dic (Y;18) (p11;p11), inv(9) (p11q13), and the points of chromosomal breakages were thought to be in the short arm of chromosome 18 and in the short arm of Y chromosome. 18p-syndrome is caused by a chromosomal deletion, and presents with a wide variety of clinical appearances. Many cases have been reported since the original descriptions by de Grouchy in 1963, though with few mentions of neurological deficits other than mental retardation. Furthermore, there have been no reports of pyramidal tract signs, weakness and focal dystonia of the lower extremities, or visual field defect, without recognizable anatomical abnormalities. Our case of 18p-syndrome is quite rare because of multiple nervous system abnormalities mentioned above, not accompanied by malformations of the central nervous system.
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PMID:[18p-syndrome with bilateral pyramidal tract signs, dystonia of the lower extremities and concentric visual field defect]. 792 61

In this report we review the data on 75 male patients with extra Y chromosome diagnosed in Leuven in the period 1968-1993 among 98,725 patients (males and females) referred for constitutional chromosomal analysis. Special attention was given to their mental performance and psychosocial functioning. 1. Fifty male with 47,XYY karyotype were diagnosed. This is very close to the incidence of XYY in newborn studies and indicates that the frequency of MR/MCA is not increased in XYY male in general. 2. In the 60 patients with "pure" Y chromosome polysomy, the most frequent indication for karyotyping was the presence of MR and/or characterological problems in the index patients. Mental retardation was mostly borderline to mild, and severe mental retardation was rare. Characterological problems, difficulties in psychosocial integration and psychiatric problems were found in 86% of the mentally retarded versus 24% of the mentally normal men. 3. The 48,XXYY syndrome is characterized by markedly frequent and severe behavioural and psychiatric problems.
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PMID:XYY syndrome and other Y chromosome polysomies. Mental status and psychosocial functioning. 858 46

Trisomy is the leading known cause of mental retardation and pregnancy loss in humans, yet virtually nothing is known of the underlying nondisjunctional mechanisms. Since studies of other organisms suggest an association between centromere size or sequence and meiotic nondisjunction, we recently initiated studies to examine the effect of centromere size variation on human nondisjunction. In the present report, we summarize studies correlating variation in the size of the Y-chromosome centromere with sex chromosome nondisjunction. In one set of studies, we used pulsed-field gel electrophoresis to estimate Y-chromosome alpha-satellite array lengths in normal males, and correlated these values with Y-chromosome sperm disomy levels as determined by fluorescence in situ hybridization. In a second set of studies, we determined the Y-chromosome alpha-satellite array length of 47,XYY males, since the karyotypes of these individuals are a consequence of Y chromosome nondisjunction. Neither set of studies provided evidence for an effect of Y-chromosome alpha-satellite array length on Y-chromosome nondisjunction. Thus, if there is an association between Y-chromosome centromere size and nondisjunction, the effect is subtle and below the detection levels of the present study or involves extreme size variants that were not represented in the present study population.
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PMID:The effect of Y-chromosome alpha-satellite array length on the rate of sex chromosome disomy in human sperm. 864 3

Fluorescence in situ hybridization (FISH) using biotin labeled X- and Y-chromosome DNA probes was utilized in the analysis of 23 sex chromosome-derived markers. Specimens were obtained through prenatal diagnosis, because of a presumptive diagnosis of Ullrich-Turner syndrome, mental retardation, and minor anomalies or ambiguous genitalia; three were spontaneous abortuses. Twelve markers were derived from the X chromosome and eleven from the Y chromosome; this demonstrates successfully the value and necessity of FISH utilizing DNA probes in the identification of sex chromosome markers. Both fresh and older slides, some of which had been previously G-banded, were used in these determinations. We have also reviewed the literature on sex chromosome markers identified using FISH.
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PMID:Sex chromosome markers: characterization using fluorescence in situ hybridization and review of the literature. 921 60

In 46,XY individuals, testes are determined by the activity of the SRY gene (sex-determining region Y), located on the short arm of the Y chromosome. The other genetic components of the cascade that leads to testis formation are unknown and may be located on the X chromosome or on the autosomes. Evidence for the existence of several loci associated with failure of male sexual development is indicated by reports of 46,XY gonadal dysgenesis associated with structural abnormalities of the X chromosome or of autosomes (chromosomes 9, 10, 11 and 17). In this report, we describe the investigation of a child presenting with multiple congenital abnormalities, mental retardation and partial testicular failure. The patient had a homogeneous de novo 46,XY,inv dup(9)(pter-->p24.1::p21.1-->p23.3::p24.1-->qter) chromosome complement. No deletion was found by either cytogenetic or molecular analysis. The SRY gene and DSS region showed no abnormalities. Southern blotting dosage analysis with 9p probes and fluorescent in situ hybridisation data indicated that the distal breakpoint of the duplicated fragment was located at 9p24.1, proximal to the SNF2 gene. We therefore suggest that a gene involved in normal testicular development and/or maintenance is present at this position on chromosome 9.
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PMID:Failure of testicular development associated with a rearrangement of 9p24.1 proximal to the SNF2 gene. 952 82

A de novo complex chromosome rearrangement (CCR) involving chromosomes 1, 6, 7, 15 and Y was detected in a boy with mental retardation, short stature, and microcephaly. Fluorescence in situ hybridisation (FISH) with whole chromosome painting libraries, band-specific cosmids and telomeric probes was essential for the characterisation of the rearrangement. The CCR was shown to be the result of at least nine chromosomal breaks and involved the alternating insertion of two segments of the short arm of chromosome 1 and two segments of the long arm of chromosome 6 into a novel derived chromosome 7. A non-reciprocal translocation between the distal short arm of the same chromosome 7 and the distal long arm of the Y chromosome was also found, together with a paracentric inversion of the long arm of chromosome 15. The only detectable imbalance was a deletion of the heterochromatic Yq telomeric region. FISH investigations in this case have revealed an additional complexity in this CCR, which has implications for reproductive risk assessment and genetic counselling.
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PMID:A de novo complex chromosomal rearrangement with nine breakpoints characterized by FISH in a boy with mild mental retardation, developmental delay, short stature and microcephaly. 1046 23

The Y chromosome is one of the human chromosomes carrying significant amount of constitutive heterochromatin. To investigate the prevalence of Y chromosome polymorphism and its clinical significance in Taiwan, we analyzed the Y chromosome among 6,286 unrelated males by G-banding and, if necessary, fluorescence in situ hybridization studies. The prevalence of the Y chromosome variants were: large Y (Yq+) 3.6%, pericentric inverted Y [inv(Y)] 0.27%, and small Y (Yq-) 0.59%, respectively. More than 99% of those variants were from their biological fathers. The incidence of the Y polymorphisms was similar in three groups: children with mental retardation, other chromosomal aberrations or multiple congenital anomalies, and normal controls. The Yq12 heterochromatin region may contribute to the variation in Y chromosome length. The prevalence of inv(Y) and Yq+ was higher than those in the white population. Our results conclude that there are no indications that Yq+, inv(Y) and Yq- are connected with any deviations in intelligence or with an increased risk of physical malformations or other chromosomal disorders, which is of great help for genetic counseling.
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PMID:Study of human Y chromosome polymorphism in Taiwan. 1091 May 37


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