Recurrent molecular abnormalities in type VII collagen in Southern Italian patients with recessive dystrophic epidermolysis bullosa.

In this study we searched for mutations in the type VII collagen gene (COL7A1) in 10 families from Southern Italy with severe generalised recessive dystrophic epidermolysis bullosa using PCR amplification of genomic DNA, heteroduplex analysis and direct nucleotide sequencing. Our principal aim was to identify any recurrent mutations in COL7A1 that might facilitate future mutation detection strategies in this population. Three recurrent COL7A1 mutations were delineated in six of the 10 families: a frameshift mutation in exon 4, 497insA, was detected in three affected individuals from three families, a deletion mutation at the acceptor splice site of intron 114/exon 115, 8441-14del21, was found in five patients in three of the families, and an intron 49 acceptor splice site mutation, 4783-1 G-to-A, was identified in three subjects in two families (GenBank accession no, L02870). Haplotype analyses showed evidence for propagation of common ancestral mutant COL7A1 alleles for each of these recurrent mutations. These results contribute significantly to understanding the nature of COL7A1 pathology in patients from Southern Italy and in designing future approaches to mutation detection.

Routine clinical application of the FRAXA Pfu PCR assay: limits and utility.

Fragile X genotype is characterized by the excessive amplification of an unstable region of DNA: a trinucleotide repeat CGG of variable copy number present in the FRAXA locus. Methods based on polymerase chain reaction (PCR) amplification of the CGG repeat region could facilitate the development of a rapid screening assay. Unfortunately, amplification across CGG repeats can be inefficient and unreliable due to their 100% G + C base composition. The utility of the exonuclease-deficient Pfu polymerase for amplification and detection of the CGG repeats at the FRAXA locus has been reported. In the present study we analysed the utility of a Pfu PCR assay as a rapid initial screening method to rule out a diagnosis of fragile X syndrome in males with mental retardation. Affected males did not show any amplification products or a smear of amplification products between 350 and 550 bp. Only 10% of affected male samples did not show any amplification products, while the vast majority showed the amplification smear. The amplification smears represent a serious drawback of the method, since they cannot be distinguished from the amplification products of normal samples after separation in 1% agarose gel. Several modifications of the PCR conditions were attempted to eliminate this problem, but none was appropriate for clinical applications. However, the problem was easily solved by using a higher resolution electrophoretic system that allows a clear distinction of normal bands from pathological smears. We tested the specificity of the Pfu PCR assay, followed by an improved MetaPhor gel electrophoretic separation of PCR products, on 50 samples from normal males and 24 samples form affected males. The results showed that this method is a rapid, sensitive and specific assay for the exclusion of fragile X syndrome diagnosis in mentally retarded males.

Plectin deficiency results in muscular dystrophy with epidermolysis bullosa.

We report that mutation in the gene for plectin, a cytoskeleton-membrane anchorage protein, is a cause of autosomal recessive muscular dystrophy associated with skin blistering (epidermolysis bullosa simplex). The evidence comes from absence of plectin by antibody staining in affected individuals from four families, supportive genetic analysis (localization of the human plectin gene to chromosome 8q24.13-qter and evidence for disease segregation with markers in this region) and finally the identification of a homozygous frameshift mutation detected in plectin cDNA. Absence of the large multifunctional cytoskeleton protein plectin can simultaneously account for structural failure in both muscle and skin.

Micromegakaryocytes in a patient with partial deletion of the long arm of chromosome 11 [del(11)(q24.2qter)] and chronic thrombocytopenic purpura.

Thrombocytopenia or pancytopenia is frequently reported in patients with partial 11q deletion but there are no reports on bone marrow morphology of these patients. We report on a patient with partial deletion of the long arm of chromosome 11 [del(11)(q24.2qter)] and its classical clinical manifestations including chronic thrombocytopenic purpura in whom micromegakaryocytes were found in the bone marrow aspirate. This is the first report of the presence of micromegakaryocytes in the bone marrow of a patient with 11q deletion. Accurate examination of the bone marrow of other patients with the 11q deletion may clarify whether the observation of micromegakaryocytes is common in these patients. Micromegakaryocytes may indicate a defect of development. Two genes for two DNA binding proteins that are likely to be involved in hematopoiesis map in the 11q region: Ets-1, that maps to 11q24, close to D11S912, and the nuclear-factor-related-kB gene that maps to 11q24-q25. It is possible that these genes, when present in only one copy, result in thrombocytopenia or pancytopenia as observed in this patient.

Genetic linkage to the type VII collagen gene (COL7A1) in 26 families with generalised recessive dystrophic epidermolysis bullosa and anchoring fibril abnormalities.

To strengthen the evidence for genetic linkage to COL7A1, we have studied 26 generalised recessive dystrophic epidermolysis bullosa (EB) families of British, Italian, Irish, and South African origin. We chose two linkage markers, a COL7A1 PvuII intragenic polymorphism and a highly informative anonymous microsatellite marker, D3S1100, which maps close to the COL7A1 locus at 3p21.1-3. Diagnosis was established by family history, clinical examination, immunofluorescence, and ultrastructural studies. The PvuII marker was informative in 16 families with a maximum lod score (Zmax) of 3.51 at recombination fraction (theta) = 0. The D3S1100 microsatellite was informative in 24 out of 25 families with Zmax = 6.8 at theta = 0.05 (Z = 4.94 at theta = 0) and no obligatory recombination events. These data strongly suggest that COL7A1 mutations cause EB in these families and, combined with previous studies, indicate locus homogeneity. The importance of anchoring fibrils for dermal-epidermal adhesion is further underlined. D3S1100 may later prove useful in prenatal diagnosis of this disease, if used in combination with other markers.

Acrofacial dysostoses: review and report of a previously undescribed condition: the autosomal or X-linked dominant Catania form of acrofacial dysostosis.

The acrofacial dysostoses (AFDs) are a heterogeneous group of disorders combining defects of craniofacial and limb development. The predominantly preaxial form is called Nager AFD, the predominantly postaxial form of AFD (POADS) is also known as the Genée-Wiedemann or Miller syndrome. The former appears to be about twice as common as the latter with well-documented autosomal dominant and recessive occurrences in both conditions. Only 1 AD occurrence of POADS is known, but 5 sets of sibs are suggestive of AR inheritance. Heterogeneity of apparently nonsyndromal AFD of both types is powerful support for the hypothesis that the AFDs are polytopic field defects arising during blastogenesis. Six other previously described forms of AFD include the AFD syndrome of Kelly et al. (AR), the Rodríguez or Madrid form of AFD (AR or XLR), the Reynolds or Idaho form of AFD (AD), the Arens or Tel Aviv type of AFD (AF?), the presumed AR AFD syndrome of Richieri-Costa et al., and the AD Patterson-Stevenson-Fontaine syndrome. Here we review the AFDs and report on a previously apparently undescribed autosomal or X-linked dominant form of AFD with mental retardation in a Sicilian mother and her 4 sons.

[The newborn infant of the diabetic mother: the clinical findings in 431 subjects]. / Il neonato di madre diabetica: rilievi clinici su 431 soggetti.

431 newborns of diabetic mothers (NDM) were studied between the years 1980 and 1990. They were divided into two groups: a first group of 227 patients born from mother with gestational diabetes mellitus; a second group of 204 patients born from mother with pregestational diabetes mellitus. The first and the second group were subdivided into two subgroups: the A, referring to the period 1980-85, and the B, referring to the period 1986-90. Subgroups B were characterized by a better metabolic control of pregnancies. Our protocol consisted of anamnestic study, clinical, metabolic, instrumental examinations and clinical follow-up for a period ranging from 1 to 10 years. The study of our data suggests that embryo-feto-neonatal mortality doesn't show significantly difference between the first and the second group and between subgroups A and B. The percentage of preterm infants was significantly more elevated in the second group, the percentage of full-term newborns was significantly higher in the first group. The incidence of cesarean sections was significantly higher in subgroups B. Mean birthweight was more elevated in the first group and the incidence of macrosomia was higher in subgroups A. The incidence of asphyxia, hypotonia, seizures, transient cardiomegaly, transient hypoglycaemia and hypocalcemia, was higher in subgroups A, without significant difference between the first and the second group. Congenital anomalies were heterogeneous and there were no significant difference between the first and the second group. Only the incidence of congenital cardiopathies was significantly more elevated in the second group. At follow-up neurologic sequelae were mainly characterized by behavioural anomalies.

Unstable translocations: a new case?

A female patient with Down syndrome due to unbalanced Robertsonian translocation (14;21) is reported. A different Robertsonian translocation involving a chromosome no. 14 was observed in her father, who was a carrier of a balanced Robertsonian t(13;14), while the maternal karyotype was normal. Hypotheses about the origin of the translocation in the daughter are discussed.

[Investigations on herpes 1 and 2 infections]. / Indagini sull'infezione-malattia da herpes 1 e 2.

The authors carried out a research on diffusion of Herpes virus 1 and 2 investigating specific serous antibodies over a sample of 1660 women living in Roma and in the surrounding area aged between 14 and 40 years; 595 of them were suspected to have an Herpes infection. The results of this research confirmed an high frequency of Herpes 1 and 2 infection in the examined sample. In order to correlate better the outcomes obtained by the investigation on the suspected sample 102 vaginal smear, executed on women suspected to have a developed infection, have been examined. The issues confirmed that it's useful to execute cytoimmunologic research in so far as such method seems to give more certainty in infection and disease identification than seroconversion investigation.

[Toxoplasmic infection-disease in suspected cases and healthy subjects]. / La infezione-malattia toxoplasmica in soggetti sospetti e clinicamente sani.

A short epidemiological presentation of the toxoplasmic infectious disease in our country on suspected cases compared with a clinically healthy group shows the importance of the phenomenon, especially for its various preventative and therapeutic implications.