首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 0 毫秒
1.
Canine muscular dystrophy: confirmation of X-linked inheritance   总被引:4,自引:0,他引:4  
The genetic basis of muscular dystrophy in golden retriever dogs was investigated by means of experimental matings and cytogenetic studies. An affected male golden retriever was mated to three normal females, producing an F1 generation of six males and 14 females, all of which were clinically normal. Of six F1 females retained for breeding, all were shown to be carriers of muscular dystrophy in outcrosses to unrelated normal male dogs or in backcrosses to the affected male golden retriever. In outcrosses of carrier females, three of seven male and none of nine female offspring were affected, as expected under the X-linked recessive hypothesis. Backcrosses of F1 females to their affected sire also yielded results that are consistent with this hypothesis: 15 of 32 males and 5 of 17 females had muscular dystrophy. Cytogenetic studies of a carrier female, an affected male offspring, and a normal male sibling revealed no detectable abnormalities of the X chromosome.  相似文献   

2.
3.
The X-linked dominant form of Charcot-Marie-Tooth disease (CMTX) is associated with mutations in a gene coding for the gap-junction protein connexin 32 (Cx32). We screened 32 CMT families with a pedigree pattern suggestive of X-linked inheritance for the presence of mutations in the coding region of Cx32 by direct sequencing. Five of the families had a CMT1 diagnosis, 24 had a CMT2 diagnosis and 3 patients had an unspecified CMT. Eight families with a Cx32 point mutation were detected. Five different mutations (four of them published previously) were found in six CMT2 families and one mutation was found in a sporadic CMT1 male patient. One of the mutations, Met194Val, is among the first described in the fourth transmembrane domain of Cx32. Two CMT2 families and the sporadic CMT1 patient had the same mutation, Arg22Gln. An additional, previously unpublished mutation, Arg75Trp, was found in a male patient with unspecified CMT, who subsequently was verified to have a variant Klinefelter syndrome with 48,XXYY karyotype. Our findings show the difficulty in distinguishing CMTX patients from CMT1 and CMT2 patients, and they emphasize the need for Cx32 mutation screening in families previously diagnosed with CMT2. Received: 29 November 1996 / Revised: 17 February 1997  相似文献   

4.
X-linked inheritance of Alport syndrome: family P revisited.   总被引:3,自引:3,他引:3       下载免费PDF全文
Likelihood analysis using two autosomal/X-linked mixed models confirmed that Alport syndrome is an X-linked dominant disease in a large Utah kindred, family P. The penetrance was estimated as .85 in females and 1.0 in males. Previously reported abnormal segregation ratios were reexamined. No excess of affected offspring of affected parents was found. Nor was the penetrance in daughters of asymptomatic carrier mothers found to be lower than in the daughters of symptomatic mothers, although the sample size was small. However, there was an unexplained deficiency of sons of affected fathers. There was no deficiency of sons of affected mothers, nor was there a deficiency of males in the kindred.  相似文献   

5.
6.
The literature concerning eye migration and cranial development during flatfish metamorphosis is briefly reviewed and found to give rise to five hypotheses to account for the phenomenon. The cranial morphology of specimens of Soleidae, Pleuronectidae, Scophthalmidae and Bothidae in pre-metamorphic, metamorphic and post-metamorphic stages are described. The mechanisms by which eye migration and cranial development occur are discussed and some aspects of pleuronectiform relationships are briefly commented on.  相似文献   

7.
Although familial recurrences of Rett syndrome (RTT) comprise only approximately 1% of the reported cases, it is these cases that hold the key for the understanding of the genetic basis of the disorder. Families in which RTT occurs in mother and daughter, aunt and niece, and half sisters are consistent with dominant inheritance and variable expressivity of the phenotype. Recurrence of RTT in sisters is likely due to germ-line mosaicism in one of the parents, rather than to recessive inheritance. The exclusive occurrence of classic RTT in females led to the hypothesis that it is X-linked and may be lethal in males. In an X-linked dominant disorder, unaffected obligate-carrier females would be expected to show nonrandom or skewed inactivation of the X chromosome bearing the mutant allele. We investigated the X chromosome inactivation (XCI) patterns in the female members of a newly identified family with recurrence of RTT in a maternal aunt and a niece. Skewing of XCI is present in the obligate carrier in this family, supporting the hypothesis that RTT is an X-linked disorder. However, evaluation of the XCI pattern in the mother of affected half sisters shows random XCI, suggesting germ-line mosaicism as the cause of repeated transmission in this family. To determine which regions of the X chromosome were inherited concordantly/discordantly by the probands, we genotyped the individuals in the aunt-niece family and two previously reported pairs of half sisters. These combined exclusion-mapping data allow us to exclude the RTT locus from the interval between DXS1053 in Xp22.2 and DXS1222 in Xq22.3. This represents an extension of the previous exclusion map.  相似文献   

8.
Linkage analysis of 72 pedigrees by the maximum-likelihood method provides evidence of linkage between HLA and the hypothesized multiple sclerosis susceptibility gene (MSSG) for both the dominant and recessive models of inheritance and for penetrance values ranging from 5%--65% (or higher). This MSSG, if it exists, is most likely located at 15%--20% recombination units from the HLA complex, probably on the B-D side. The analysis also shows that there is no heterogeneity in the estimates of linkage, and lod scores are not artifically inflated because of the association of multiple sclerosis (MS) with HLA-B7.  相似文献   

9.

Background

Systemic sclerosis (SSc), a progressive disease characterized by excessive accumulation of connective tissue components. Although most patients have long survival, some of them progress rapidly to death. Pulmonary system involvement and pulmonary hypertension are the most frequent cause of death. When the patient with SSc is to be operated, the anesthetic procedure could be a serious problem. In this article, we report a combined spinal – epidural technique in a patient with progressive SSc and the anesthetic considerations that could be recommended for these patients.

Case presentation

A 68-year-old woman who had a history of progressive systemic sclerosis, pulmonary fibrosis, kyphoscoliosis and decreased oral apertura underwent total hip arthroplasty. This operation was performed successfully under combined spinal epidural anesthesia.

Conclusion

Systemic sclerosis is a complex disease that involves multiple organ systems. Every aspects of anesthetic care may be altered or hindered by the pathogenesis of disease. Although the choice of regional or general anesthesia is unclear, to choose combined spinal epidural anesthesia may be useful.  相似文献   

10.
11.
12.
Osteopathia striata with cranial sclerosis (OSCS), conductive hearing impairment and a characteristic facial appearance is the clinical manifestation in carrier women of an X-linked disease. We report on a family with typical OSCS in the mother, a maternal aunt and the grandmother, and multiple severe malformations in the son. He was affected by cranial sclerosis with frontal bossing, conductive hearing impairment, cleft palate, thoracic dysplasia, mesenterium commune with non-rotation of the gut, anal atresia, bilateral cutaneous syndactyly of 3rd and 4th fingers, duplication of the distal phalanx of 2nd and 3rd fingers on the right, bilateral fibular aplasia with clubfeet, developmental retardation, epileptic seizures, hypothyroidism, and hypertrophic pyloric stenosis. The X-inactivation pattern in peripheral leucocytes of one informative carrier woman was random. Our case and several literature reports confirm that males which are hemizygous for the OSCS trait suffer from a dysmorphic syndrome with characteristic multiple malformations as a distinct entity. There is, at present, no reason to assume genetic heterogeneity with an autosomal dominant OSCS variant.  相似文献   

13.
VACTERL/VATER association is typically a sporadic disorder. We present data on inheritance in 78 probands with VACTERL association, and show that 9% of probands have a primary relative with at least one component feature of VACTERL association. The prevalence of component features in first-degree relatives is significantly higher than expected in the general population, which has implications for counseling of affected families and for research into possible etiologies.  相似文献   

14.
Fibrous dysplasia (FD) is a relatively uncommon disorder that affects primarily the cranial region; its occurrence in the cranial base in combination with hindbrain herniation and aneurysmal bone cyst (ABC) constitutes an extremely rare condition. We report a case of polyostotic fibrous dysplasia with progressive occipital, temporal, and clival involvement. Clinical findings and differential diagnosis with special emphasis on the imaging features were discussed. A small posterior fossa volume has been thought to lead to hind brain herniation. The resultant obstruction to the CSF pathways at the level of the foramen magnum has been implicated in the development and subsequent progression of syringobulbia.  相似文献   

15.
We found evidence of autosomal dominant hereditary transmission of sulcus vocalis. Four dysphonic patients from three generations of the same family were submitted to videolaryngoscopic examination (three patients) and to direct laryngoscopy (one patient) to diagnose the hoarseness. Sulcus vocalis was diagnosed in all four patients. The finding of four affected individuals in three generations, with vertical transmission affecting man and women, is more consistent with autosomal dominant inheritance pattern; it is an etiological model that we propose for the sulcus vocalis in this pedigree.  相似文献   

16.
17.
The amyloid hypothesis for Alzheimer's disease: a critical reappraisal   总被引:1,自引:0,他引:1  
The amyloid hypothesis has been the basis for most work on the pathogenesis of Alzheimer's disease. Recent clinical trials based on this hypothesis have been inconclusive. In this article I review the current status of the hypothesis and suggest that a major scientific need is to understand the normal function of amyloid-β precursor protein (APP) and think how this may relate to the cell death in the disease process.  相似文献   

18.
19.
Heterochromatin: new possibilities for the inheritance of structure   总被引:24,自引:0,他引:24  
Significant portions of the eukaryotic genome are heterochromatic, made up largely of repetitious sequences and possessing a distinctive chromatin structure associated with gene silencing. New insights into the form of packaging, the associated histone modifications, and the associated nonhistone chromosomal proteins of heterochromatin have suggested a mechanism for providing an epigenetic mark that allows this distinctive chromatin structure to be maintained following replication and to spread within a given domain.  相似文献   

20.
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号