Neuropsychological studies in families with fragile-X negative X-linked mental retardation.

Neuropsychological studies were performed in 82 subjects of 12 families with x-linked, fragile X negative, mental retardation (MR). Subjects were examined with Wechsler tests (WPPSI, WISC-R or WAIS, according to their capabilities), Progressive Matrices, Bender or Santucci and memory tests. Physical findings in 5 families were characterised by micro-orchidism (MiO), microcephaly (MiC), short stature (SS) and non-specific facial features (XMR +/- MiO +/- MiC +/- SS). The 11 males with MR had a very low IQ, ranging from 13 to 37 (mean 21.2 +/- 8.8); this did not constitute a profile definition. Among the females of their families, 4 had subnormal or borderline IQ, respectively 74, 66, 38 and 37. A second group (2 families) had MiO but with normal stature and occipito-frontal circumference (XMR +/- MiO). The 7 males with MR had an IQ ranging from 24 to 43 (mean 35.1 +/- 5.8) and showed frequently better results in performance than in verbal subtests. In these 2 families, 5 females had subnormal or borderline IQ, respectively 77, 72, 71, 70 and 20. In the 5 families of the third group, XMR +/- MaO (fraX-), several affected males had macro-orchidism (MaO) and facial changes similar to those of fragile X syndrome. IQ variability, also in the same family (e.g.: the 3 brothers of family 3 had, respectively, an IQ of 26, 28 and 68; and 2 brothers of family 1 had an IQ of 13 and 63) and different profiles. Two females were severely affected (IQ 16 and 24), while another 4 had an IQ, respectively, of 63, 69, 71 and 72.     

Two brothers with Martsolf''s syndrome.

Two brothers affected by a syndrome consisting of short stature, hypogonadism, and severe mental retardation are reported. The syndrome shares the features of that described by Martsolf et al in two brothers born to a consanguineous Polish Jewish couple. Although our patients' parents are Sephardic Jews, they deny consanguinity. These observations and personal knowledge of another affected Jewish boy raise the question of whether Martsolf's syndrome is a new entity that should be included in the group of those that affect mainly Jewish people, and whether its pattern of inheritance is X linked recessive or autosomal recessive limited to males.     

Four brothers with mental retardation,spastic paraplegia and palmoplantar hyperkeratosis. A new syndrome?

We report a Caucasian family in which four males out of a total of seven siblings are mentally retarded. Three of the affected individuals have spasticity in the lower limbs (spastic paraplegia), pes cavus deformity of both feet and an abnormal gait. In addition, they show palmar and plantar hyperkeratosis. The other male sibling does not have spasticity, but his lower limb reflexes are abnormally brisk and he has slight pes cavus deformity. He also shows hyperkeratosis of his palms and soles and is less mentally retarded that his brothers. The mother of the affected boys has normal intelligence, but has plantar hyperkeratosis and a strong facial resemblance to her retarded sons. Her three daughters are normal. The pedigree information is compatible with a sex-linked mode of inheritance and no specific biochemical or cytogenetic abnormality has been found in the affected individuals. There have been no previous reports of hyperkeratosis palmaris et plantaris in other inherited spastic syndromes.     

Two Dutch brothers with Borrone dermato-cardio-skeletal syndrome

In 1993, Borrone et al. described two Italian brothers affected by a syndrome of severe acne, mitral valve prolapse, dysmorphic facies, and Scheuermann-like changes of the vertebral column. Since then, no further cases have been reported. Here, we report on two Dutch brothers with many features suggestive of this rare syndrome.     

X-linked dysmorphic syndrome with mental retardation

We present a dysmorphic syndrome in eight males of the same family (four brothers, three cousins and one uncle) that is characterised by: mental retardation, facial dysmorphia, abnormal growth of teeth, skin dimple at the lower back, clinodactyly, patella luxation, malformation of lower limbs, abnormalities of the fundus of the eye and subcortical cerebral atrophy. These physical defects do not correspond to any previously described syndrome, which suggests that it is a new syndrome. According to the model of heredity this syndrome could be due to a mutant gene situated in the X-chromosome.     

Townes-Brocks syndrome associated with mental retardation

A 43-year-old female was admitted to our hospital for polydipsia and hyperglycemia. She had total blindness and globes were not recognized by inspection, indicating clinical anophthalmia. Physical examination revealed short stature, obesity, prematurely gray hair, shortness of fingers and toes, syndactyly, and multiple dental caries. Laboratory examination showed hyperglycemia, increased glycosilated hemoglobin (HbA₁c) and insulin resistance on euglycemic glucose clamp. Blunted growth hormone (GH) secretion was shown in response to insulin-induced hypoglycemia, arginine infusion, and GH-releasing hormone (GHRH) loading test, and in 24 h spontaneous GH profile. Magnetic resonance imaging (MRI) and computed tomography (CT) showed dysostosis of orbit, defect of optic nerve, enlarged suprasellar cistern, and prolonged pituitary stalk. This may be the first report of a unique case with GH deficiency accompanied by clinical anophthalmia, hypoplastic orbits, digital dysplasia, short stature, obesity, and diabetes mellitus. © 1996 Wiley-Liss, Inc.     

DISC1 duplication in two brothers with autism and mild mental retardation

Crepel A, Breckpot J, Fryns J‐P, De la Marche W, Steyaert J, Devriendt K, Peeters H. DISC1 duplication in two brothers with autism and mild mental retardation. We describe the identification and delineation of an inherited 2.07 Mb microduplication in 1q42.2 in two brothers with autism and mild mental retardation. Since this duplication was not present in 1577 Belgian persons, we consider this as an extremely rare variant which has the potential to provide further insight into the genetics of autism. The duplication contains seven genes including the DISC1 gene, an interesting candidate gene that has been associated to schizophrenia, bipolar disorder, autism and Asperger syndrome. In this report we describe additional analyses undertaken to investigate the causal relationship of the duplication to the autism phenotype. We conclude that the 1q42.2 microduplication probably confers susceptibility to autism in the current family. This study is a typical illustration of the difficult interpretation of causality of a very rare variant in neuropsychiatric disease and the challenge of genetic counselling in a particular family.     

Two siblings with mental retardation and progressive spasticity

Nicolaides P, Baraitser M, Brett EM. Two siblings with mental retardation and progressive spasticity.
Clin Genet 1993: 43: 312–314. © Munksgaard, 1993
We describe two siblings with a progressive form of spastic paraplegia, seizures and non-progressive mental retardation.     

CAG repeat contraction in the androgen receptor gene in three brothers with mental retardation.

We report on three brothers with mental retardation and a contracted CAG repeat in the androgen receptor (AR) gene. It is known that expansion of the CAG repeat in this gene leads to spinal and bulbar muscular atrophy (SBMA or Kennedy disease); however, contracted repeats have not yet been implicated in disease. As the range of the length of CAG repeats in the AR gene, like those of other genes associated with dynamic mutations, follows a normal distribution, the theoretical possibility of disease at both ends of the distribution should be considered.     

Alopecia/mental retardation syndrome

We report on an African-American patient with alopecia universalis, microcephaly, hypogonadism, and mental and growth retardation, and compare his phenotype to others with recessive alopecia/mental retardation syndromes in the literature. Our patient represents the first case reported from nonconsanguineous African-American parents. © 1995 Wiley-Liss, Inc.     

A novel nonsense mutation in CUL4B gene in three brothers with X‐linked mental retardation syndrome

Badura‐Stronka M, Jamsheer A, Materna‐Kiryluk A, Sowińska A, Kiryluk K, Budny B, Latos‐Bieleńska A. A novel nonsense mutation in CUL4B gene in three brothers with X‐linked mental retardation syndrome. Cabezas syndrome (MIM 300354) is a recently identified syndromic form of X‐linked mental retardation (XLMR) caused by mutations in the CUL4B gene. In total, nine XLMR families carrying mutations in the CUL4B gene have been described to date. Here, we present a detailed clinical phenotype of three affected brothers of Polish descent. Based on the symptoms, we made a clinical diagnosis of Cabezas syndrome, which was subsequently confirmed by identification of a novel nonsense mutation (c.2107A→T, p.703K→X) in exon 18 of the CUL4B gene. The mutation was inherited from an asymptomatic mother and was present in all three affected brothers. The patients presented with typical features of Cabezas syndrome, such as severe mental retardation, speech impairment, hyperactivity, seizures, intention tremor, inguinal hernia, small feet, and craniofacial dysmorphism. In addition to previously described symptoms, syndactyly of the second and third toes and skin manifestations (hyperhydrosis and keratosis pilaris) were present in our cases. Our report provides further support that Cabezas syndrome is a recognizable syndromic form of XLMR. We conclude that the CUL4B gene should be screened in males with severe speech impairment and primary intention tremor, especially if characteristic facial dysmorphism is also present.     

Two brothers with the Marden-Walker syndrome: case report and review

Two brothers with blepharophimosis, congenital joint contractures, and mental retardation characteristic of the Marden-Walker syndrome are described. This sib pair strengthens the case for autosomal recessive inheritance of the syndrome.     

Two Robertsonian translocations in a boy with mental retardation

An 8-year-old boy with mental retardation was found to be a mosaic, showing three different cell lines, 46,XY/46,XY,-21,+t(q21q21)/45,XY,-13,-21,+t(q13q21) in cultured peripheral blood cells.     

Zimmerman-Laband syndrome and profound mental retardation

A young man was diagnosed as having Zimmerman-Laband syndrome (ZLS) on the basis of gingival fibromatosis and absence of nails on thumbs and halluces in addition to other anomalies. He also had profound mental retardation.     

A new X-linked mental retardation syndrome

We have studied a three-generation family with 11 moderately to severely retarded males and three mildly retarded females (presumably manifesting carriers). The patients have a phenotype different from that of all other previously described types of X-linked MR (XLMR). These include short stature, macrocephaly, "coarse" facial appearance including prominent forehead and supraorbital ridges, hypertelorism, broad nasal tip with anteverted nostrils, and thick lips. All postpubertal males had macroorchidism (volume greater than 25 ml). Chromosomes were normal including fragile X analysis. X-ray findings of skull, spine, and hands were normal. The intellectually normal relatives do not resemble their affected relatives except for increased head size and testicular size. These findings suggest a new variant of XLMR different from fragile X-linked MR, the Coffin-Lowry syndrome, and other XLMR conditions.