Further evidence that de novo missense and truncating variants in ZBTB18 cause intellectual disability with variable features.

Identification of rare genetic variants in patients with intellectual disability (ID) has been greatly accelerated by advances in next generation sequencing technologies. However, due to small numbers of patients, the complete phenotypic spectrum associated with pathogenic variants in single genes is still emerging. Among these genes is ZBTB18 (ZNF238), which is deleted in patients with 1q43q44 microdeletions who typically present with ID, microcephaly, corpus callosum (CC) abnormalities, and seizures. Here we provide additional evidence for haploinsufficiency or dysfunction of the ZBTB18 gene as the cause of ID in five unrelated patients with variable syndromic features who underwent whole exome sequencing revealing separate de novo pathogenic or likely pathogenic variants in ZBTB18 (two missense alterations and three truncating alterations). The neuroimaging findings in our cohort (CC hypoplasia seen in 4/4 of our patients who underwent MRI) lend further support for ZBTB18 as a critical gene for CC abnormalities. A similar phenotype of microcephaly, CC agenesis, and cerebellar vermis hypoplasia has been reported in mice with central nervous system-specific knockout of Zbtb18. Our five patients, in addition to the previously described cases of de novo ZBTB18 variants, add to knowledge about the phenotypic spectrum associated with ZBTB18 haploinsufficiency/dysfunction.

Copy number variations in three children with sudden infant death.

Sudden death of an infant is a devastating event that needs an explanation. When an explanation cannot be found, the case is labeled as sudden infant death syndrome or unclassified sudden infant death. The influence of genetic factors has been recognized for sudden infant death, but copy number variations (CNVs) as potential risk factors have not been evaluated yet. Twenty-seven families were enrolled in this study. The tissue specimens from deceased children were obtained and array-based comparative genomic hybridization (array-CGH) experiments were performed on the genomic DNA isolated from these specimens using Agilent Technologies Custom 4 x 44K arrays. Quantitative polymerase chain reaction experiments were performed to confirm the overlapping duplication and deletion region in two different cases. A de novo CNV is detected in 3 of 27 cases (11%). In case 1, an approximately 3-Mb (chr 8: 143,211,215-qter) duplication on 8q24.3-qter and a 4.4-Mb deletion on the 22q13.3-qter (chr 22: 45,047,068-qter) were detected. Subtelomeric chromosome analysis of the father and the surviving sibling of case 1 showed a balanced reciprocal translocation, 46,XY,t(8;22)(q24.3;q13.3). A 240-kb (chr 6: 26,139,810-26,380,787) duplication and a 1.9-Mb deletion (chr 6: 26,085,971-27,966,150) at chromosome 6p22 were found in cases 2 and 3, respectively. Array-CGH and conventional cytogenetic studies did not reveal the observed CNVs in the parents and the siblings of cases 2 and 3. The detected CNVs in cases 2 and 3 encompassed several genes including the major histone cluster genes. Array-CGH analysis may be beneficial during the investigations after sudden infant death.

Factors in decision making following genetic counseling for pre-natal diagnosis of de novo chromosomal rearrangements.

A retrospective survey of genetic counselors was conducted in order to identify practice patterns and factors that influence a patient's decision making when a de novo translocation is diagnosed pre-natally. Different variables that influence patients' decisions about pregnancy management were assessed and compared. Specifically, the type of rearrangement and/or knowledge of the breakpoints, risks provided for abnormal outcome, anxiety, fetal ultrasound findings and personal reasons for parental decisions were evaluated. Our findings suggest that patient anxiety level significantly predicts pregnancy management decisions. This information may be of benefit in identifying potential areas of education for genetic counselors as well as other health care providers.

Carrier screening for Gaucher disease in couples of mixed ethnicity.

With the advent of mutational analysis for Gaucher disease, carrier screening has been incorporated into many Jewish genetic disease screening programs. Frequencies and mutations for Gaucher disease in non-Jewish populations are less well established and the detection rate of carriers are lower. Testing is problematic for resolving residual risk in a couple of mixed ethnicity. We report the testing choices made by 20 consecutive couples of mixed ethnicity where the Ashkenazi Jewish partner was identified to be a Gaucher disease gene carrier. Carrier studies of the non-Jewish partner were elected as follows: DNA studies alone, 5 (25%); enzymatic assay, 2 (10%); both, 6 (30%); no carrier studies, 7 (35%). Of the 7 couples not electing carrier studies, one was not in a pregnancy and 6 elected prenatal diagnosis in lieu of parental testing by enzymatic analysis of amniocytes. One couple elected parental carrier studies as well as prenatal diagnosis. All couples electing prenatal Gaucher determination had amniocentesis for other indications as well (4, advanced maternal age; 4, parental anxiety). We conclude that Gaucher screening is feasible for couples of mixed ethnicity if appropriate counseling and testing are offered.

Maternal uniparental disomy of chromosome 16 and body stalk anomaly.

We report on a fetus with placental trisomy 16, maternal uniparental disomy (UPD), and body stalk anomaly. Body stalk anomaly is a rare, fatal developmental abnormality consisting of a defective abdominal wall with abdominal organs in a sac outside the abdominal cavity covered by amnion adherent to the placenta with absence or severe shortness of the umbilical cord. Trisomy 16 was identified in the placenta in all cells. Amniocentesis was karyotypically normal. Parental origin studies showed maternal UPD for chromosome 16 in post-termination fetal tissue. The cause of the body stalk anomaly is not clearly defined. There are no other reports of placental karyotype or UPD investigations with body stalk anomaly. To our knowledge, this is the first report of placental trisomy 16, UPD in fetus, and body stalk anomaly, suggesting placental insufficiency or imprinting effects as cause of this anomaly. Am. J. Med. Genet. 94:284-286, 2000.

Epidermolysis bullosa, pyloric atresia, and obstructive uropathy: a report of two case reports with molecular correlation and clinical management.

The epidermolysis bullosa-pyloric atresia-obstructive uropathy (EB-PA-OU) association is a rare, but well-described multisystem disease. While the prognosis at this time is still poor, an increasing number of patients are surviving to adolescence with aggressive care. It is important to understand this syndrome in order to anticipate medical complications and offer preventive strategies where possible. Prompt and expectant management of obstructive uropathy is crucial in these patients. Evidence of ureterovesicular obstruction may require bowel diversion, as excision of the obstructed ureterovesicular junction with reimplantation is often associated with a high risk of reobstruction. Many newborns succumb to sepsis or dehydration and electrolyte imbalance. Those infants who survive need close monitoring for the development of obstructive uropathy, failure to thrive, protein-losing enteropathy, respiratory compromise, and increased susceptibility to invasive infections. Once a clinical diagnosis is made, mutational analysis can confirm it and facilitate genetic counseling, as recurrence risks are 25% for this autosomal recessive condition. Mutational analysis enables direct genetic testing and accurate prenatal diagnosis. As more patients are studied, genotype/phenotype correlations may be possible.

Early prenatal ultrasound diagnosis of cleidocranial dysplasia.

A woman was referred in the first trimester of her third pregnancy because of a family history of cleidocranial dysplasia. An ultrasound examination at 14 weeks 4 days revealed a fetus with appropriate biometric measurements. However, the clavicles were noted to be hypoplastic and the cranium appeared less well ossified than expected for gestational age, suggesting the diagnosis of cleidocranial dysplasia. On subsequent examination at 21 weeks, the findings were essentially unchanged. Induced vaginal delivery owing to decreased amniotic fluid volume occurred at 37 weeks, and a female weighing 3200 g was delivered. The infant had clinical and X-ray signs of cleidocranial dysplasia.

Common trisomy mosaicism diagnosed in amniocytes involving chromosomes 13, 18, 20 and 21: karyotype-phenotype correlations.

Karyotype-phenotype correlations of common trisomy mosaicism prenatally diagnosed via amniocentesis was reviewed in 305 new cases from a collaboration of North American cytogenetic laboratories. Abnormal outcome was noted in 10/25 (40%) cases of 47,+13/46, 17/31 (54%) cases of 47,+18/46, 10/152 (6.5%) cases of 47,+20/46, and in 49/97 (50%) cases of 47,+21/46 mosaicism. Risk of abnormal outcome in pregnancies with less than 50% trisomic cells and greater than 50% trisomic cells were: 26% (4/15) versus 60% (6/10) for 47,+13/46, 52% (11/21) versus 75% (6/8) for 47,+18/46, 4.5% (6/132) versus 20% (4/20) 47,+20/46, and 45% (27/60) versus 59% (22/37) for 47,+21/46. Phenotypically normal liveborns were observed with mean trisomic cell lines of 9.3% for 47,+13/46, 8.6% for 47,+18/46, 27% for 47, +20/46, and 17% for 47,+21/46. Cytogenetic confirmation rates were 46% (6/13 cases) for 47,+13/46 mosaicism, 66% (8/12 cases) for 47, +18/46, 10% (10/97 cases) for 47,+20/46, and 44% (24/54 cases) for 47,+21/46. There were higher confirmation rates in pregnancies with abnormal versus normal outcome: 50% versus 44% for 47,+13/46 mosaicism, 100% versus 33% for 47,+18/46, 66% versus 7% for 47, +20/46, and 55% versus 40% for 47,+21/46. Repeat amniocentesis is not helpful in predicting clinical outcome. It may be considered when there is insufficient number of cells or cultures to establish a diagnosis. Fetal blood sampling may have a role in mosaic trisomy 13, 18, and 21 as the risk for abnormal outcome increases with positive confirmation: 1/5 (20%) normal cases versus 5/8 (62%) abnormal cases. High resolution ultrasound examination(s) is recommended for clinical correlation and to facilitate genetic counselling.

Diagnostic analysis of the Rubinstein-Taybi syndrome: five cosmids should be used for microdeletion detection and low number of protein truncating mutations.

Rubinstein-Taybi syndrome (RTS) is a malformation syndrome characterised by facial abnormalities, broad thumbs, broad big toes, and mental retardation. In a subset of RTS patients, microdeletions, translocations, and inversions involving chromosome band 16p13.3 can be detected. We have previously shown that disruption of the human CREB binding protein (CREBBP or CBP) gene, either by these gross chromosomal rearrangements or by point mutations, leads to RTS. CBP is a large nuclear protein involved in transcription regulation, chromatin remodelling, and the integration of several different signal transduction pathways. Here we report diagnostic analysis of CBP in 194 RTS patients, divided into several subsets. In one case the mother is also suspect of having RTS. Analyses of the entire CBP gene by the protein truncation test showed 4/37 truncating mutations. Two point mutations, one 11 bp deletion, and one mutation affecting the splicing of the second exon were detected by subsequent sequencing. Screening the CBP gene for larger deletions, by using different cosmid probes in FISH, showed 14/171 microdeletions. Using five cosmid probes that contain the entire gene, we found 8/89 microdeletions of which 4/8 were 5' or interstitial. This last subset of microdeletions would not have been detected using the commonly used 3' probe RT1, showing the necessity of using all five probes.

Short rib-polydactyly syndrome: more evidence of a continuous spectrum.

We report a fetus with radiological features of the four established types of short rib-polydactyly syndrome (SRPS). The phenotype of this fetus supports the previously suggested hypothesis that the different subtypes of the short rib and polydactyly syndrome are not single entities, but rather, part of a continuous spectrum with variable expressivity.

Cystic fibrosis carrier screening practices in an ethnically diverse region: experience of the Genetic Network of the Empire State, Puerto Rico, and the U.S. Virgin Islands.

We surveyed clinical genetics centers to assess current cystic fibrosis (CF) screening practices with regard to clinical and laboratory aspects. The survey was developed by the CF committee of the Genetics Network of the Empire State, Puerto Rico, and the U.S. Virgin Islands (GENES) to gauge changes in trends following the April, 1997, NIH Consensus Statement recommending the offering of CF carrier screening to all pregnant patients. Thirty-five of 45 Centers (78%) returned the survey, which was mailed in June, 1998. Sixteen centers currently offer population-based screening, whereas 19 centers do not. Reasons cited for not offering testing included the low risk for CF in ethnic groups served, lack of data about test sensitivity in the populations served, and the absence of CF screening policies in the current standards of care. Approximately half (56%) of genetics centers that are offering testing altered their screening policy following the NIH Consensus statement, either by offering screening to patients of higher-risk ethnicities or by offering it to all patients. Less than half of the Centers that offer routine carrier screening offer screening to all patients regardless of ethnicity. This report is an initial step in documenting and understanding the current service practices regarding CF carrier testing in a diverse region. Our conclusions: (1) Screening practices vary widely among genetic centers in the region. (2) The decision to offer routine CF carrier screening is largely based on ethnicity of the patient population served. (3) Methods used to screen pregnant women and their partners in this part of the country reflect the diversity of models employed throughout the United States. (4) CF screening practices in the GENES region have changed significantly following the April, 1997, NIH consensus statement.

The spectrum of mutations in TBX3: Genotype/Phenotype relationship in ulnar-mammary syndrome.

Ulnar-mammary syndrome (UMS) is a pleiotropic disorder affecting limb, apocrine-gland, tooth, hair, and genital development. Mutations that disrupt the DNA-binding domain of the T-box gene, TBX3, have been demonstrated to cause UMS. However, the 3' terminus of the open reading frame (ORF) of TBX3 was not identified, and mutations were detected in only two families with UMS. Furthermore, no substantial homology outside the T-box was found among TBX3 and its orthologues. The subsequent cloning of new TBX3 cDNAs allowed us to complete the characterization of TBX3 and to identify alternatively transcribed TBX3 transcripts, including one that interrupts the T-box. The complete ORF of TBX3 is predicted to encode a 723-residue protein, of which 255 amino acids are encoded by newly identified exons. Comparison of other T-box genes to TBX3 indicates regions of substantial homology outside the DNA-binding domain. Novel mutations have been found in all of eight newly reported families with UMS, including five mutations downstream of the region encoding the T-box. This suggests that a domain(s) outside the T-box is highly conserved and important for the function of TBX3. We found no obvious phenotypic differences between those who have missense mutations and those who have deletions or frameshifts.

Psychoanalytic research and the IPA: history, present status and future potential.

This paper traces the chequered history of formal psychoanalytic research within the century-long development of psychoanalysis as theory and practice. It describes the official involvement of the American Psychoanalytic Association in the support of psychoanalytic research since 1970, and of the International Psychoanalytical Association since the 1980s. In the IPA, this has consisted of the introduction at the 1987 Montreal Congress of two half-day panels on formal psychoanalytic research; in the creation in 1991 of an annual IPA Research Conference held in March at University College London; and then the creation in 1996 of an annual ten-day IPA Summer School for neophyte psychoanalytic researchers, also at UCL in London. The paper then details the inauguration by the IPA, at the 1997 IPA Congress in Barcelona, of a mechanism for funding psychoanalytic research the Research Advisory Board (RAB), and the overwhelming--and totally unanticipated--worldwide response to the initial call for proposals in the autumn of 1997. Implications of this for psychoanalysis as a discipline are sketched.

Acro-renal-ocular syndrome: expansion of the phenotype.

We report the sixth described family with acro-renal-ocular syndrome in a boy and more mildy in his mother. Severe upper limb deficiency, dysplastic kidneys, and strabismus are noted in this child in addition to developmental delay, dysplastic corpus callosum, and incomplete myelination. Developmental central nervous system (CNS) malformations have not been described in this syndrome previously and may represent an expansion of the phenotype.

Novel ITGB4 mutations in lethal and nonlethal variants of epidermolysis bullosa with pyloric atresia: missense versus nonsense.

Epidermolysis bullosa with pyloric atresia (EB-PA), an autosomal recessive genodermatosis, manifests with neonatal cutaneous blistering associated with congenital pyloric atresia. The disease is frequently lethal, but nonlethal cases have also been reported. Expression of the alpha6 beta4 integrin is altered at the dermal-epidermal basement-membrane zone; recently, mutations in the corresponding genes (ITGA6 and ITGB4) have been disclosed in a limited number of patients, premature termination codons in both alleles being characteristic of lethal variants. In this study, we have examined the molecular basis of EB-PA in five families, two of them with lethal and three of them with nonlethal variants of the disease. Mutation analysis disclosed novel lesions in both ITGB4 alleles of each proband. One of the patients with lethal EB-PA was a compound heterozygote for premature termination-codon mutations (C738X/4791delCA), whereas the other patient with a lethal variant was homozygous for a missense mutation involving a cysteine residue (C61Y). The three nonlethal cases had missense mutations in both alleles (C562R/C562R, R1281W/R252C, and R1281W/R1281W). Immunofluorescence staining of skin in two of the nonlethal patients and in one of the lethal cases was positive, yet attenuated, for alpha6 and beta4 integrins. These results confirm that ITGB4 mutations underlie EB-PA and show that missense mutations may lead to nonlethal phenotypes.

The IPA and the American Psychoanalytic Association: a perspective on the regional association agreement.

Ever since 1938 the American Psychoanalytic Association has had a special autonomous relationship within the IPA accorded to no other component organisation. This Regional Association status has had two main features: (1) total internal control over training standards and membership criteria, with no accountability to the IPA; and (2) an 'exclusive franchise', so that the IPA was barred from recognising any other component within the United States. This unique Regional Association status reflected the resolution at the time (1938) of the long-standing controversy between the IPA and the American over the issue of 'lay analysis', and remained unaltered for half a century until, with the resolution of the 3 1/2-year long law-suit against the American (and secondarily against the IPA) in 1988, the Regional Association agreement was modified (but not totally abrogated) by the American's giving up the 'exclusive franchise' aspect (thus permitting IPA recognition of psychoanalytic groups in the US organised outside the American), but still retaining its internal full control over training and membership. The meanings and consequences for psychoanalysis of this special status of the American are explored.

Genetic screening of prospective oocyte donors.

OBJECTIVE: To report our experience with genetic screening of oocyte donor candidates and to determine the frequency with which significant genetic issues are identified. DESIGN: Prospective genetic screening of oocyte donor candidates. SETTING: University hospital oocyte donation program. PATIENT(S): Women presenting consecutively as volunteer oocyte donors. INTERVENTION(S): Genetic screening was performed by pedigree analysis and laboratory studies. MAIN OUTCOME MEASURE(S): Inclusion in the oocyte donor pool based on the results of clinical evaluation and laboratory tests consisting of polymerase chain reaction based mutational analysis for cystic fibrosis carrier status, cytogenetic analysis for karyotype, enzymatic assay for Tay-Sachs disease carrier status, and complete blood count and hemoglobin electrophoresis. RESULT(S): Eight (11%) of 73 oocyte donor candidates were excluded from the donor pool because of a potentially serious genetic finding. Cystic fibrosis mutations were identified in 5 candidates (7%), abnormal karyotypes were found in 2 (3.5%), and an autosomal dominant skeletal dysplasia was identified in 1 (1.4%). CONCLUSION(S): A significant proportion of women who present as candidates for oocyte donation are inappropriate for donation because of their genetic history or genetic testing results. A thorough genetic evaluation, including a history and laboratory screening, is essential to any oocyte donation program to maximize positive outcomes in pregnancies achieved through assisted means.

A new form of complicated hereditary spastic paraplegia with cataracts, atretic ear canals and hypopigmentation.

A 16-year-old Hispanic boy born of consanguineous parents is described as having a history of cataracts, progressive lower-extremity spasticity and atrophy starting at 4 years of age, atretic ear canals with hearing dysfunction and diffuse patchy cutaneous hypopigmented areas. Clinical examination showed the typical signs of spastic paraplegia with increased tone, hyperreflexia, muscle atrophy and contractures. Sensation, autonomic and cerebellar functions were not disturbed. Neuroimaging studies were normal. Laboratory findings did not support a diagnosis of metabolic disturbance or infectious disease. This is considered a new form of complicated hereditary spastic paraplegia (HSP), transmitted presumably in an autosomal recessive pattern.