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

Jacobsen syndrome (JBS) is a haploinsufficiency syndrome caused by partial deletion of the long arm of chromosome 11. It is characterized by developmental delay (DD)/mental retardation (MR), physical growth retardation, facial dysmorphism, visceral malformations and thrombocytopenia. We report two JBS patients from China out of a total of 451 patients with unexplained DD/MR. The genotypes of these patients were compared with earlier reported patients in North America and Europe. Both patients presented with severe DD, microcephaly and facial dysmorphism; one patient had a low birth weight, congenital heart disease and structural brain abnormalities. Neither patient was thrombocytopenic at the time of diagnosis. The two deletions were 4.1 and 12.8 Mb. The 4.1 Mb deletion is the smallest of all pathogenic regions earlier reported in JBS. Therefore, the critical region underlying DD/MR might be located in the distal portion of the chromosomal segment within 4.1 Mb of the telomere. Candidate genes for DD/MR in this region include SNX19, THYN1, OPCML, NCAPD3 and NTM. One of the critical regions for craniofacial abnormalities may be within 130.3-134.4 Mb in chromosome 11q. Further analysis of Chinese JBS patients would elucidate the relation of phenotype to genotype further.
 ...
PMID:Diagnosis and fine mapping of a deletion in distal 11q in two Chinese patients with developmental delay. 2052 Jun 18

The association between fragile sites and human genetic diseases is still debatable. Although FRAXA and FRAXE have been found to be associated with mental retardation and FRA11B possibly with Jacobsen syndrome, no other autosomal fragile site has yet been found to have a direct correlation with a genetic disorder; however, the frequency of fragile sites in infertile couples has been reported to be higher than in a control group. The occurrence of a fragile site can therefore be a possible risk factor causing considerable anxiety to the clinician and probably requires follow up with appropriate genetic counseling. The present study reports heterozygosity for FRA16B in both partners of an infertile non-consanguineous couple married for 9 years. They had been referred for cytogenetic evaluation with the complaint of multiple fetal losses.
 ...
PMID:Spontaneous expression of FRA16B in a non-consanguineous couple experiencing multiple fetal losses. 2256 72

Jacobsen syndrome is a rare contiguous gene syndrome caused by partial deletion of the long arm of chromosome 11. The typical clinical manifestations include physical growth retardation, mental retardation,facial dysmorphisms, congenital heart disease, thrombocytopenia, or pancytopenia. A Thai-Australian girl was born with multiple abnormalities. Typical features and her karyotype, 46, XX, del(ll) (q23-qter), confirmed Jacobson syndrome. She had many uncommon findings including upslanting palpebral fissures, tortuousity of retinal vessels and hypogammaglobulinemia. In addition, this case also presented with protein C deficiency, which has not been reported previously in Jacobsen syndrome. The patient was treated with phototherapy, intravenous antibiotic injection, and platelet transfusion in neonatal period. Cranioplasty was performed for prevention of the increased intracranial pressure at three months of age. Surgical correction for strabismus was in the treatment plan.
 ...
PMID:Hypoimmunoglobulinemia and protein C deficiency in a girl with Jacobsen syndrome: a case report. 2431 61

E26 transformation-specific 1 (ETS1) and friend leukemia integration 1 (FLI1) are members of the ETS family of transcription factors, of which there are 28 in humans. Both genes are hemizygous in Jacobsen syndrome, an 11q contiguous gene deletion disorder involving thrombocytopenia, facial dysmorphism, growth and mental retardation, malformation of the heart and other organs, and hearing impairment associated with recurrent ear infections. To determine whether any of these defects are because of hemizygosity for ETS1 and FLI1, we characterized the phenotype of mice heterozygous for mutant alleles of Ets1 and Fli1. Fli1(+/-) mice displayed mild thrombocytopenia, as did Ets1(+/-)Fli1(+/-) animals. Fli1(+/-) and Ets1(+/-)Fli1(+/-) mice also displayed craniofacial abnormalities, including a small middle ear cavity, short nasal bone, and malformed interface between the nasal bone process and cartilaginous nasal septum. They exhibited hearing impairment, otitis media, fusions of ossicles to the middle ear wall, and deformed stapes. Hearing impairment was more penetrant and stapes malformations were more severe in Ets1(+/-)Fli1(+/-) mice than in Fli1(+/-) mice, indicating partial functional redundancy of these transcription factors during auditory development. Our findings indicate that the short nose, otitis media, and hearing impairment in Jacobsen syndrome are likely because of hemizygosity for ETS1 and FLI1.
...
PMID:Mice Haploinsufficient for Ets1 and Fli1 Display Middle Ear Abnormalities and Model Aspects of Jacobsen Syndrome. 2609 83


<< Previous 1 2