1/12. A frameshift mutation of the ED1 gene in sibling cases with X-linked hypohidrotic ectodermal dysplasia.X-linked hypohidrotic ectodermal dysplasia (XLHED; MIM 305100) is characterized by the absence or hypoplasia of hair, teeth, and sweat glands. The ED1 gene was identified as a responsive gene for XLHED. The patients were 2 Japanese brothers. Both had the same mutation in exon 1 of the ED1 gene, i.e. C deletion at nucleotide 49, which induced a frameshift starting from amino acid 17 and made a stop codon at amino acid 56, encoding the transmembrane site. The mutation caused the extracellular domain of ectodysplasin A to be completely absent. Their mother had a heterozygous allele; she congenitally lacked 1 tooth, and incisors appeared conical in form.- - - - - - - - - - ranking = 1keywords = hypoplasia (Clic here for more details about this article) |
2/12. Borjeson-Forssman-Lehmann syndrome and multiple pituitary hormone deficiency.We describe two brothers with Borjeson-Forssman-Lehmann syndrome and the 22A-->T (Lys8X) PHF6 mutation, who presented with the symptoms and signs of multiple pituitary hormone deficiency. Biochemical investigations and radiology confirmed growth hormone (GH), thyroid stimulating hormone (TSH) and adrenocorticotrophic hormone (ACTH) as well as gonadotrophin deficiency. They were also found to have optic nerve hypoplasia. This family suggests that the BFL gene product may play an important role in midline neuro-development including the hypothalamo-pituitary axis.- - - - - - - - - - ranking = 1keywords = hypoplasia (Clic here for more details about this article) |
3/12. Second female case of Myhre syndrome.Myhre syndrome is a rare disorder characterized by low birthweight, short stature, mental retardation, facial dysmorphism (blepharophimosis, midfacial hypoplasia, prognathism), heart anomalies, muscle hypertrophy, decreased joint mobility and deafness. To date 11 male cases and only one female case have been reported. This paper describes the second female case and compares the clinical and radiological findings between female and male patients.- - - - - - - - - - ranking = 1keywords = hypoplasia (Clic here for more details about this article) |
4/12. Enamel defects and Lyonization in focal dermal hypoplasia.We report a pattern of enamel hypoplasia in focal dermal hypoplasia similar to that found in females with X-linked amelogenesis imperfecta. Three cases of focal dermal hypoplasia are described, with specific focus on the oral and dental features. In these cases the teeth all had vertical grooving with notching of the incisal or cuspal tips. Also recorded were blunt roots of taurodont form with open apices and missing teeth in 1 case. Oral papillomas were present in 2 cases. The pattern of enamel defects is attributed to Lyonization, which is consistent with the pattern of skin and bone lesions typically seen in focal dermal hypoplasia. This supports the proposal that focal dermal hypoplasia is X-linked. The authors conclude that the pattern of dental defects in focal dermal hypoplasia is consistent with Lyonization.- - - - - - - - - - ranking = 199.34470088157keywords = dermal hypoplasia, focal dermal hypoplasia, hypoplasia, focal (Clic here for more details about this article) |
5/12. Index finger abnormalities in Simpson-Golabi-Behmel syndrome.Simpson-Golabi-Behmel syndrome (SGBS) is an X linked recessive overgrowth disorder in which digital abnormalities are a well-described aspect of the phenotype. We report a case with marked index finger hypoplasia and a congenital abnormality of the proximal phalanx and review the literature detailing index finger abnormalities in this condition.- - - - - - - - - - ranking = 1keywords = hypoplasia (Clic here for more details about this article) |
6/12. Complex glycerol kinase deficiency: an X-linked disorder associated with adrenal hypoplasia congenita.Complex glycerol kinase deficiency (GKD) results from the contiguous deletion on Xp21 of all or part of the gene for glycerol kinase together with that for adrenal hypoplasia congenita (AHC) and /or Duchenne muscular dystrophy (DMD). The authors present the case of a newborn whose initial issues were refractory hypoglycaemia along with hyponatremia and hyperkalemia. He also had low serum cortisol levels and raised urinary excretion of glycerol and required steroid supplementation. His creatinine phosphokinase (CPK) levels were normal. Molecular studies revealed a contiguous Xp21 deletion. Therapy in such cases must be prompt and includes correction of hypoglycaemia and dyselectrolytemia, a low fat diet and steroid replacement.- - - - - - - - - - ranking = 5keywords = hypoplasia (Clic here for more details about this article) |
7/12. Inappropriate tall stature and renal ectopy in a male patient with X-linked congenital adrenal hypoplasia due to a novel missense mutation in the DAX-1 gene.Mutations in DAX-1 gene cause congenital adrenal hypoplasia (AHC). We present a male patient affected by X-linked adrenal hypoplasia congenita due to a novel DAX-1 missense mutation. The mutation V287G affects the C-terminal end of the DAX-1 protein which plays an important role in functioning of the receptor. In addition, our patient presented an inappropriate tall stature and renal ectopy, which have not been described in AHC so far.- - - - - - - - - - ranking = 6keywords = hypoplasia (Clic here for more details about this article) |
8/12. Midline defects in FG syndrome: does tethered spinal cord contribute to the phenotype?OBJECTIVES: FG syndrome is an X-linked recessive mental retardation syndrome with ano-rectal anomalies, constipation, and occasional urinary incontinence. Because tethered spinal cord syndrome (TCS) has similar symptoms, we evaluated imaging for TCS in patients with FG syndrome. STUDY DESIGN: patients were recruited from the International FG syndrome Support Group, and an FG syndrome consensus Group reviewed clinical histories, medical records, and photographs of each responding patient. Results of cranial and spinal imaging studies were available for 12 patients. RESULTS: Of 12 boys with FG syndrome, 6 had hypoplasia of the corpus callosum, and 3 of these had TCS (all with constipation and urinary symptoms). The other 9 did not have urinary symptoms. After surgical untethering, bowel and bladder symptoms improved. CONCLUSIONS: Tethered spinal cord syndrome occurred in 25% of patients with FG syndrome associated with hypoplasia of the corpus callosum and causing bowel and bladder incontinence. A high index of suspicion is necessary for early diagnosis, and timely intervention results in significant improvement in symptomatology.- - - - - - - - - - ranking = 2keywords = hypoplasia (Clic here for more details about this article) |
9/12. Identification of novel mutations of the DAX-1 gene in patients with X-linked adrenal hypoplasia congenita.OBJECTIVE: X-linked adrenal hypoplasia congenita (AHC) is a condition clinically featuring adrenal insufficiency and hypogonadotropic hypogonadism caused by mutations of DAX-1. This study was undertaken to characterize the molecular defects of DAX-1 in 3 unrelated Korean patients with AHC. patients AND methods: Patient 1 is a 6-year-old boy who presented with a salt-losing adrenal crisis in the neonatal period. Patient 2 is a 3-year-old boy who manifested aspiration pneumonia and adrenal insufficiency at the age of 1 month. Patient 3 is a 7-year-old boy who developed an adrenal crisis at the age of 3 days. In each of these patients, DAX-1 was analyzed by direct dna sequencing after polymerase chain reaction amplification of the entire coding region. RESULTS: Direct sequencing of DAX-1 revealed two novel mutations, 1156_1157delCT in patient 1 and another novel nonsense mutation W105X in patient 2. Patient 3 had complete deletion of DAX-1. In patient 3, serum transaminases and creatine kinase levels were elevated while the glycerol kinase activity of leukocytes was decreased. Markedly elevated glycerol excretion was detected by urine organic acid analysis. Patient 3 was diagnosed as Xp21 contiguous gene syndrome associated with deletions of the entire IL1RAPL, GK genes and the C-terminal region of DMD gene. CONCLUSIONS: Two novel mutations of DAX-1 were detected in 2 unrelated patients with AHC, and complete deletion of DAX-1 in a patient with Xp21 contiguous gene syndrome who also presented with glycerol kinase deficiency, Duchenne muscular dystrophy, and AHC.- - - - - - - - - - ranking = 5keywords = hypoplasia (Clic here for more details about this article) |
10/12. Cerebral, cerebellar, and colobomatous anomalies in three related males: sex-linked inheritance in a newly recognized syndrome with features overlapping with Joubert syndrome.We present a so far unrecognized X-linked mental retardation syndrome with features overlapping with Joubert syndrome (JBS). Two brothers showed hypotonia, mental retardation, ocular abnormalities with impaired vision and colobomas and a breathing pattern compatible with JBS. neuroimaging revealed cerebellar vermis hypoplasia and ventriculomegaly. A tentative diagnosis of JBS was made, and autosomal recessive inheritance considered most likely. In a subsequent pregnancy that occurred after artificial donor insemination, ultrasound in the 22nd week revealed a Dandy-Walker malformation and hydrocephaly. At autopsy at 34 weeks of gestation, the male infant showed cerebellar vermis aplasia and abnormalities of the brainstem and cerebral cortex. He was considered to have the same disorder as his two half-brothers. This renders the pedigree highly suggestive of X-linked inheritance. The clinical symptoms of this syndrome resemble JBS. However, the absence of the molar tooth sign and the X-linked inheritance do not support JBS. We propose the name X-linked cerebral-cerebellar-coloboma syndrome to distinguish the two disorders. Differentiation of the two disorders is especially important in genetic counseling, where artificial donor insemination may be considered as a means of reducing the recurrence risk, or when female relatives of the patient are concerned.- - - - - - - - - - ranking = 1keywords = hypoplasia (Clic here for more details about this article) |
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