摘要:

AbstractUsing trisomy 19 produced experimentally in mice, we examined the genetic control of the survival of trisomic fetuses. Data are presented that show clearly that the prevalence of experimentally produced trisomy 19 in mice, observed on day 15 of gestation, is genetically influenced. There appeared to be an inverse relationship between strain differences in frequency of trisomy 19 fetuses and frequency of fetal loss, suggesting that the observed differences in prevalence of trisomy 19 fetuses resulted from differential survival of trisomic fetuses.

ISSN:0148-7299    

DOI:10.1002/ajmg.1320260402

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1987

数据来源: WILEY

摘要:

AbstractCongenital complex chromosome rearrangements (CCR) compatible with life are rare in man. Thus patients with CCR usually present considerable diagnostic difficulties both clinically and cytogenetically. We studied a 12‐year‐old mentally retarded male with minor congenital anomalies as described below and his first‐degree relatives. The propositus had an unbalanced karyotype with eight break points and seven derivative chromosomes; two deletions, del(6) (q25 → qter) and del(14) (q31 → qter), and four translocations, t(2;11), t(5;15), t(6;11), t(6;20) were present. Parental chromosomes were normal; however, the mother had a few metaphases with abnormal chromosomes suggestive of chromosome instability; These findings and a review of reported patients with CCR are presented with regard to speculations about etiology, pathogenesis, phenotypic expression, and prognosis. Physicians should be aware of CCR and broader indications for cyto‐genetic studies appear warranted in view of

ISSN:0148-7299    

DOI:10.1002/ajmg.1320260403

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1987

数据来源: WILEY

ISSN:0148-7299    

DOI:10.1002/ajmg.1320260404

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1987

数据来源: WILEY

摘要:

AbstractIn the NIH Collaborative Perinatal Project, a prospective study of over 53,000 pregnant women and their offspring, 71 single‐born children (13.33/10,000) were found to have a non‐syndromal neural tube defect (NTD). A family history was present in only one case. The group of individuals with NTD was compared to a group of 400 randomly selected non‐malformed control infants. Of over 50 maternal factors studied the following showed significant association with NTD in the offspring: diabetes mellitus; organic heart disease; lung disease; and diuretic, antihistamine, and sulfonamide use. The interval between the termination of the immediately previous pregnancy and the start of the proband pregnancy was significantly shorter in mothers of NTD children than in mothers of control infants. The risk for NTD was also significantly increased if the immediately previous pregnancy was a spontaneous abortion. There was no increased risk for NTDs among sibs of children with major malformations such as tracheo‐esopha‐geal “dysraphism,” cleft lip/palate, or renal agenesis. NTDs are apparently etiologically

ISSN:0148-7299    

DOI:10.1002/ajmg.1320260405

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1987

数据来源: WILEY

摘要:

AbstractThis report presents the pathologic anatomy of a prospectively collected series of 36 anencephalic infants. This series provides an opportunity to investigate the epidemiology of organ system pathology in anencephaly (AN) as well as other facets of its natural history. AN infants had a mean gestational age 2.5 weeks younger than normal controls, though birthweight was normal for gestational age. Nearly 1/3 of the liveborn infants with AN died within 15 minutes, 2/3 within 3 hours; 3 AN infants survived to 48 hours. Details and discussions of the pathologic findings and their physiologic significance are presented. Regarding those AN infants who received detailed neurologic examinations, correlations are made between the brain pathology and neurologic function prior to death.

ISSN:0148-7299    

DOI:10.1002/ajmg.1320260406

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1987

数据来源: WILEY

摘要:

AbstractGenetic counselling is recommended for parents of children with neural tube defects (NTDs) to inform them of the recurrence risks and the option of prenatal diagnosis. British Columbia provides an excellent site to examine the use by parents of genetic counselling services for NTDs. Genetic services for the entire province are centralized, and there is virtually complete ascertainment of all NTD births. The resulis from this study indicate that use of genetic counselling services is influenced by the type of NTD present and whether the index case was live or stillborn. Genetic counselling is most often sought after the birth of a liveborn infant with spina bifida.

ISSN:0148-7299    

DOI:10.1002/ajmg.1320260407

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1987

数据来源: WILEY

摘要:

AbstractWe describe a girl with extreme growth retardation of prenatal onset, short limbs, and somewhat unusual facial appearance. She represents the 6th patient with osteodysplastic primordial dwarfism type II. The distant consanguinity of the parents of this patient suggests possible autosomal recessive inheritance.

ISSN:0148-7299    

DOI:10.1002/ajmg.1320260408

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1987

数据来源: WILEY

摘要:

AbstractWe have studied a mother and son with a previously apparently undescribed syndrome of microcephaly, eye defects, small ears, mild mental deficiency, and short stature. The syndrome appears to be an autosomal or X‐linked dominant trait. The cat eye syndrome, blepharophimosis or Kohn‐Romano syndrome, Rieger syndrome, and other disorders are discussed in relationship to this ent

ISSN:0148-7299    

DOI:10.1002/ajmg.1320260409

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1987

数据来源: WILEY

摘要:

AbstractWe report on two clinically, neurologically normal relatives of a boy affected by adrenoleukodystrophy (ALD); they were found repeatedly to have the biochemical defect of an ALD hemizygote. The assay consisted in the determination of very‐long‐chain fatty acids in lyophilized and reconstituted plasma.While no evidence of neurologic disease (leukodystrophy or myeloneuropathy) was present in these hemizygotes, adrenocortical insufficiency provoking compensatory high ACTH release was found in both. These findings should be taken into consideration when counseling families in which cases with clinically expressed ALD are represented in several generati

ISSN:0148-7299    

DOI:10.1002/ajmg.1320260410

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1987

数据来源: WILEY

摘要:

AbstractCongenital heart defects (CHD) represent a heterogeneous group of disorders caused by chromosome abnormalities, mendelian disorders, teratogenic expo‐sures, and unknown etiologic mechanisms. A large group of various isolated defects is presumably multifactorial in origin. Previous studies of familial risks for specific anatomic defects obtained from clinical series may include significant biases and obscured pathogenic relationships. In this population‐based study we analyzed all cases of CHD in infants and a control birth cohort in the Baltimore‐Washington area. The rates of CHD were defined for first‐degree relatives of cases with isolated defects, grouped by a pathogenic classification scheme. Pre‐currence risks were found to vary among the groups, and risks for flow lesions were higher than previously reported. The sibling precurrence risk for hypoplastic left heart syndrome (13.5%) was not significantly different from that expected for an autosomal recessive mechanism; the risks for different types of ventricular septal defects (VSD) varied among mechanistic groups. The results indicate that the additive multifactorial model does not adequately account for the risks in all forms of isolated CHD of unknown

ISSN:0148-7299    

DOI:10.1002/ajmg.1320260411

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1987

数据来源: WILEY