Omphalocele in trisomy 3q: further delineation of phenotype

We report a case of a patient with omphalocele, dysmorphic features, and mild developmental delay associated with a chromosomal aberration. Chromosome studies showed that the propositus carries a maternally derived unbalanced translocation der(4)t(3;4)(q27.3;q32.3), resulting in trisomy for region 3q27.3-->qter and monosomy for 4q32.3-->qter. Because the association between dup3q and omphalocele has been reported in several cases, we analyzed the data on 93 previously reported patients with partial trisomy of the long arm of chromosome 3 and compared the clinical features between the cases. The imbalance of chromosome 3 in the patient was further defined by fluorescence in situ hybridization (FISH) studies using bacterial artificial chromosome (BAC) clones. BAC clone RP11-171N2 was identified as a breakpoint-spanning clone in the patient and his mother. Based on our comparative analysis, we have delineated that the smallest region of overlap (SRO) associated with omphalocele is from BAC 171N2 to 3qter. We hypothesize that the SRO contains a gene(s) important in normal abdominal wall development and is of potential interest for further investigation.

Gershoni-Baruch syndrome: report of a new family confirming autosomal recessive inheritance

Gershoni-Baruch syndrome is a multiple congenital malformation complex characterized by omphalocele, diaphragmatic hernia, cardiovascular abnormalities, and radial ray defects. Autosomal recessive inheritance is suggested. We describe two additional cases from a single family (sister and brother) delivered through termination at 23 and 9 weeks of gestation, respectively. The first fetus showed a spectrum of schisis defects without any limb involvement while the second bore mainly malformations of hands and feet. The occurrence of two different syndromes in the same family is highly improbable, but, considering both malformation complexes as possible manifestations of the same disease, a diagnosis of Gershoni-Baruch syndrome appears the most reasonable. These new familial cases bring further support to the hypothesis of an autosomal recessive inheritance of this syndrome.

Donnai-Barrow syndrome: four additional patients

In 1993, Donnai and Barrow reported a new syndrome in two sets of sibs and in an unrelated child, including diaphragmatic hernia, exomphalos, absent corpus callosum, hypertelorism, myopia, and sensorineural deafness. Since then, only four similar patients have been documented. We describe four additional patients, including two sibling pairs from healthy parents. This report firmly establishes this syndrome as a distinct clinical entity and provides further evidence for its previously postulated autosomal recessive inheritance.

[Fetal examination of first trimester abortions]

INTRODUCTION

Rather few papers are about first trimesters pathology. The reason of this roots in the technical difficulties. The first trimesters pathology can not be separated from prenatal diagnostics.

OBJECTIVES

The authors summarized the molecular basis of embryology, malformations, and published cases that had been diagnosed prenatally.

MATERIALS AND METHODS

In the I. Department of Obstetrics and Gynecology, Semmelweis University in Budapest between 1995. and 2000. altogether sixty embryos 70 gms or smaller were examined.

RESULTS

Malformations included neural tube defects, disorders of twinning, body stalk defect, chromosome aberrations, hydrops, omphalocele and gastroschisis.

CONCLUSIONS

Examination of early embryos may discover many results on the fields of prenatal diagnosis and the pathomechanism of developmental abnormalities.

Prenatal diagnosis of double autosomal mosaicism (47,XX,+8/47,XX,+14): phenotype and molecular cytogenetic analysis on different tissues

A female fetus with multiple congenital anomalies was found to have double autosomal mosaicism, 47,XX,+8/ 47,XX,+14 on chromosome analysis via amniocentesis. At delivery, the proband displayed dysmorphic features of hypertelorism, micrognathia, low set ears, cleft palate, clubfeet, omphalocele, absent gallbladder and congenital heart defects. Fluorescence in situ hybridization demonstrated a marked discrepancy in cell line populations in the tissues examined.

Omphalocele in three generations with autosomal dominant transmission

We report a family with nine subjects over three generations affected with an omphalocele requiring surgical intervention within the first few days of life. Because of the vertical transmission and male to male inheritance in our family, we conclude that an autosomal dominant gene caused the omphalocele in the affected family members. The paternal great grandfather of the proband was not clinically affected but produced two children with omphaloceles with different spouses.

Risk factors for congenital umbilical hernia in German Fleckvieh

Risk factors for congenital umbilical hernias were investigated in German Fleckvieh calves up for sale at livestock markets. Data from 53,105 calves were collected from 77 livestock auctions in 1996 and 1997. The overall incidence of congenital umbilical hernia was 1.8%. A significant influence on incidence was exerted by the sex of the calf, the occurrence of multiple births, the market place/market date, the sire and the sire line. The proportion of Red Holstein blood in the calf, the dam's lactation number, gestation length, 305 day milk performance and the herd milk level were not significant factors. Herdmate averages for calves differed significantly in their incidence. Heritability estimates on the liability scale for congenital umbilical hernia were about 0.4 and progeny groups of sires at risk for congenital umbilical hernia were in the range 0.1% to 14.2%. The segregation pattern could not be explained either by an autosomal recessive or by an autosomal dominant monogenic model. It seems likely that more than one gene locus is involved in the underlying genetic mechanism. Breeders should be aware of the genetic implications of congenital umbilical hernias.

Risk factors in congenital abdominal wall defects (omphalocele and gastroschisi): a study in a series of 265,858 consecutive births

The aim of this study was to describe the prevalence at birth of two abdominal wall defects (AWD), omphalocela and gastroschisis and to identify possible etiologic factors. The AWD came from 265,858 consecutive births of known ouome registered in the registry of congenital malformations of Strasbourg for the period 1979 to 1998. Request information on the child, the pregnancy, the parents and the family was obtained for cases and for controls. Hundred five cases with AWD were analysed, 55.2 % were omphalocele and 44.8 % were gastroschisis. The mean prevalence rate for omphalocele was 2.18 per 10,000 and for gastroschisis 1.76 per 10,000. Associated malformations were found in 74.1 % of omphalocele compared with 53.2 % of gastroschisis; 29.3 % of fetuses with omphalocele had an abnormal karyotype, 44,8 % had a recognizable syndrome, association or an unspecified malformation pattern; 51.0 % of fetuses with gastroschisis had additional malformations that were not of chromosomal origin, but 1 case. Antenatal ultrasound examination was able to detect 39 (67.2 %) cases of omphaloceles and 27 (57.4 %) cases of gastroschisis. In 30 (51.7 %) cases of omphalocele and in 7 (14.9 %) cases of gastroschisis parents opted for termination of pregnancy. The overall survival rate was 14 (24.1 %) for omphalocele and 30 (63.8 %) for gastroschisis. Weight, length and head circumference at birth of infants with AWD were less than those of controls. The weight of placenta of infants with AWD was not different from the weight of placenta of controls. Gastroschisis was associated with significantly younger maternal age than omphalocele. Pregnancies with AWD were more often complicated by threatened abortion, oligohydramnios and polyhydramnios. Mothers of children with AWD took more often medication during pregnancy than mothers of controls.

Bidirectional transcriptional activity of PGK-neomycin and unexpected embryonic lethality in heterozygote chimeric knockout mice

In an effort to create a conventional knockout mouse model for multiple endocrine neoplasia type 1 (MEN1), we targeted disruption of the mouse Men1 gene through homologous recombination in ES cells. Men1 exons 2-4 were replaced by a PGK-neomycin cassette inserted in the opposite direction of Men1 transcription (Men1(MSK/+)). Unexpectedly, the Men1 conventional knockout was lethal in heterozygous, chimeric animals. Analysis of embryos revealed late gestational lethality with some embryos showing omphalocele. This was a very surprising phenotype, given that humans and mice that are heterozygotes for loss of function mutations in MEN1 are phenotypically normal except for a risk of endocrine tumors. Northern analysis of Men1(MSK/+) embryonic stem cell RNA revealed the presence of an abundant, novel transcript of 2.1 kb, in addition to the expected wild-type transcripts of 2.7 kb and 3.1 kb. RT-PCR analysis identified this aberrant transcript as arising from the antisense strand of the PGK promoter. We hypothesize that this transcript is producing either a toxic effect at the RNA level, or a dominant negative effect through the production of an amino-terminal truncated protein product. This example serves as a cautionary reminder that mouse knockouts using PGK-neo may sometimes display phenotypes that reflect more than just the loss of function of the targeted gene.

Anuria, omphalocele, and perinatal lethality in mice lacking the CD34-related protein podocalyxin

Podocalyxin is a CD34-related sialomucin that is expressed at high levels by podocytes, and also by mesothelial cells, vascular endothelia, platelets, and hematopoietic stem cells. To elucidate the function of podocalyxin, we generated podocalyxin-deficient (podxl(-/)-) mice by homologous recombination. Null mice exhibit profound defects in kidney development and die within 24 hours of birth with anuric renal failure. Although podocytes are present in the glomeruli of the podxl(-/)- mice, they fail to form foot processes and slit diaphragms and instead exhibit cell--cell junctional complexes (tight and adherens junctions). The corresponding reduction in permeable, glomerular filtration surface area presumably leads to the observed block in urine production. In addition, podxl(-/)- mice frequently display herniation of the gut (omphalocele), suggesting that podocalyxin may be required for retraction of the gut from the umbilical cord during development. Hematopoietic and vascular endothelial cells develop normally in the podocalyxin-deficient mice, possibly through functional compensation by other sialomucins (such as CD34). Our results provide the first example of an essential role for a sialomucin in development and suggest that defects in podocalyxin could play a role in podocyte dysfunction in renal failure and omphalocele in humans.

Van der Woude syndrome with mental retardation: case report

A report of a four and half-year old African patient with Van der Woude syndrome and mental retardation is reported. In addition to cleft lip/palate, hypodontia and lower lip pits; features consistent with Van der Woude syndrome, he manifested features consistent with growth and mental retardation. A genetic basis for these associated features can only be determined by detailed karyotype studies.

Heart, brain, and body wall defects in mice lacking calreticulin

Calreticulin is a ubiquitously expressed protein, which has been implicated in a large number of cellular functions, including calcium storage and signaling, protein folding, and cell attachment. To examine the role of calreticulin during in vivo development, mice deficient in calreticulin were generated by targeted inactivation of the calreticulin gene. Calreticulin-deficient mutants die in utero, mostly in late gestation. Half of these embryos had decreased cardiac cell mass, associated with increased apoptosis of cardiac myocytes. In vitro differentiation cultures of calreticulin-deficient embryonic stem cells resulted in fewer embryoid bodies with contractile activity than cultures derived from calreticulin +/- stem cells (P < 0.001). Sixteen percent of the mutants exhibited exencephaly secondary to a defect in neural tube closure. Embryos surviving until Embryonic Day 16.5 had omphalocele. Lack of calreticulin did not influence survival of embryonic fibroblasts under various endoplasmic reticulum stress conditions. However, calreticulin did influence cell migration in a calcium- and substrate-dependent manner. We conclude that calreticulin is not essential during the early stages of embryonic development, but is important for the development of heart and brain and for ventral body wall closure. The observed abnormalities are compatible with a role of calreticulin in the modulation of cellular calcium signaling.

Sibs with anencephaly, anophthalmia, clefts, omphalocele, and polydactyly: hydrolethalus or acrocallosal syndrome?

Major characteristics of the acrocallosal syndrome include severe mental retardation, agenesis or hypoplasia of the corpus callosum, and polydactyly of fingers and toes. In the past few years, anencephaly has also been noted, together with other midline defects. We report on a nonconsanguineous, Norwegian couple with a history of two pregnancies with a male and a female fetus, respectively, with anencephaly, median cleft lip and palate, omphalocele, and preaxial polydactyly, suggesting the diagnosis of the acrocallosal syndrome. Both fetuses also lacked eyes and nose, a finding not previously reported in the acrocallosal syndrome. Microphthalmia has been reported in the hydrolethalus syndrome, which may be caused by mutations in the same gene as the acrocallosal syndrome. The present report adds support to the hypothesis that the acrocallosal and hydrolethalus syndromes may be allelic conditions. The family history is consistent with autosomal recessive inheritance.

Two sibs with Malpuech syndrome

We report on two Italian brothers with facial clefting, hypertelorism, urogenital anomalies including micropenis, shawl scrotum, hearing loss, caudal appendage, and umbilical hernia. We have evaluated the two cases as Malpuech syndrome. This is an extremely rare autosomal recessive syndrome.

Congenital anterior abdominal wall defects in the north of England, 1986-1996: occurrence and outcome

The aim was to describe trends in prevalence, maternal age-specific prevalence, associated anomalies, clinical outcomes and the sensitivity of antenatal diagnosis of congenital anterior abdominal wall defects (in particular gastroschisis and exomphalos). Data were identified from a population-based register of major congenital abnormalities in the Northern health region of England, the Northern Congenital Abnormality Survey (NorCAS), between 1986 and 1996. 296 cases were notified; there were 133 cases of gastroschisis, 98 exomphalos, 30 limb-body wall defects and 23 other anterior abdominal wall defects. 12 cases could not be classified. In 19 (6 per cent) the initial diagnosis was changed following case review. 30 (30.6 per cent) cases of exomphalos were associated with a chromosomal anomaly compared with 1 (0.8 per cent) case of gastroschisis. The total prevalence for the 11 years was 6.33 (95 per cent CI=5.57-7.08) per 10 000 live births, still births and terminations of pregnancy, and the overall birth prevalence was 4.30 (95 per cent CI=3.68-4.93) per 10 000 live births and still births. For gastroschisis, there was a significant increase over the study period in both the total prevalence (1.48 in 1986 to 5.29 per 10 000 in 1996; chi(2)=8.41, p=0.00433) and the birth prevalence (1.48 in 1986 to 4.72 per 10 000 in 1996; chi(2)=7.42, p=0.00644), but there was no such significant increase for exomphalos (total prevalence chi(2)=2.29, p=0.13055; birth prevalence chi(2)=0.16, p=0.69348). The maternal age-specific prevalence was highest in the 11-19 year age group for gastroschisis but in the 35-39 year age group for exomphalos. Fewer pregnancies with gastroschisis resulted in a termination and a greater proportion of cases were alive at one year compared with exomphalos. The sensitivity of abnormality detection by ultrasonography was 75 per cent and 77.3 per cent for gastroschisis and exomphalos, respectively. Antenatal diagnosis improved from 47.4 per cent during 1986-91 to 80 per cent between 1992-96 for gastroschisis (chi(2)=5.7, p=0.00169), and from 55.6 per cent to 68.8 per cent for isolated exomphalos, although this increase was not significant. Total and birth prevalence of gastroschisis increased in the Northern region between 1986 and 1996. For exomphalos, there was a trend towards an increase in total prevalence and towards a decrease in birth prevalence. This decreasing trend has been accompanied by improvements in antenatal detection and subsequent termination of cases of exomphalos associated with other anomalies.

A new lethal syndrome of exomphalos, short limbs, and macrogonadism

We report a new lethal multiple congenital abnormality (MCA) syndrome of exomphalos, short limbs, nuchal web, macrogonadism, and facial dysmorphism in seven fetuses (six males and one female) belonging to three unrelated families. X rays showed enlarged and irregular metaphyses with a heterogeneous pattern of mineralisation of the long bones. Pathological examination showed adrenal cytomegaly, hyperplasia of Leydig cells, ovarian stroma cells, and Langherans cells, and renal microcysts. We suggest that this condition is a new autosomal recessive MCA syndrome different from Beckwith-Wiedemann syndrome, especially as no infracytogenetic deletion or uniparental disomy of chromosome 11 was found.

Partial trisomy of chromosome 6q: an interstitial duplication of the long arm

We report on a 5-year-old girl with a de novo interstitial duplication of chromosome 6q21-q23 and delayed development and speech with distinctive minor facial anomalies including a "carp" mouth. Fluorescence in situ hybridization using a chromosome 6 paint probe confirms that the extra material is of chromosome 6 origin. This further delineates the dup(6q) syndrome and the manifestations due to the specific duplicated chromosomal region involved.

Outcome of prenatally diagnosed anterior abdominal wall defects

One hundred consecutive cases of confirmed anterior abdominal wall defect, identified prenatally in the Oxford Prenatal Diagnosis Unit over 11 years, were studied. Fifty nine per cent of cases were suspected omphaloceles and 41% suspected gastroschisis. Fifty four per cent of omphaloceles were accompanied by other defects compared with 5% of those with gastroschisis. Overall, 29% of fetuses with omphalocele had an abnormal karyotype, and of those with another abnormality identified on scan (excluding four cases with no karyotype performed), 54% had an abnormal karyotype. Of the 27 cases with suspected isolated omphalocele, 14 were live born, all of whom have survived. If the 11 whose parents opted for termination of pregnancy are excluded, survival to birth was 88%. Six of the suspected isolated omphaloceles have Beckwith Wiedemann syndrome (BWS). Eight (57%) of the live born babies with omphaloceles had major problems up to the age of 2, but only one (7%) has long term major problems. This child has BWS and is deaf. Of the 39 cases of suspected isolated gastroschisis, 33 (85%) pregnancies resulted in live birth and one in neonatal death after surgery. Survival rate (excluding terminated pregnancies) was 97%. Gastroschisis was associated with a younger maternal age than omphalocele (p < 0.001) and lower birthweight centile (p < 0.01). Fifteen per cent of the gastroschisis babies had major problems up to the age of 2 years and 12% long term developmental problems. Ninety three per cent of the omphalocele babies and 88% of those who had gastroschisis have no long term problems. Over the study period there have been major changes in scanning equipment and expertise. Since 1991 no woman with a suspected isolated lesion has opted for termination of pregnancy.

Beckwith-Wiedemann syndrome in a child with chromosome 18q deletion

Molecular genetic investigation of a female infant with Beckwith-Wiedemann syndrome (BWS) showed loss of IGF2 imprinting but no evidence of uniparental disomy. In addition, a deletion of chromosome 18q22.1 was identified in this infant without clinical features of 18q-syndrome (microcephaly, short stature, hypotonia). The association of a chromosome 18 deletion and BWS may be coincidental or may indicate the location of a trans activating regulator element for maintenance of IGF2 imprinting.