1/7. holoprosencephaly, hypertelorism, and ectrodactyly in a boy with an apparently balanced de novo t(2;4) (q14.2;q35).A holoprosencephaly, hypertelorism, and ectrodactyly syndrome (HHES) was described in three previous cases in whom chromosomes were apparently normal. We report on a 3-year-old boy with HHES and a de novo apparently balanced t(2;4)(q14.2;q35) confirmed by fluorescent in situ hybridization. He had severe growth and mental retardation, lobar holoprosencephaly, hypertelorism, microphthalmos, and iris, choroid, and retina colobomata. Less-severe facial involvement correlates with the semilobar type of holoprosencephaly; limb defects consisted of foot ectrodactyly and syndactyly. All previous HHES cases were sporadic and of unknown cause. A cryptic imbalance secondary to the translocation (2;4) in our patient may explain the phenotype.- - - - - - - - - - ranking = 1keywords = hybridization (Clic here for more details about this article) |
2/7. Recurrent digital fibroma, focal dermal hypoplasia, and limb malformations.Recurrent digital fibroma of infancy generally is considered a sporadic tumor of childhood. We describe the case of a mother with recurrent digital fibroma at a young age who gave birth to a daughter with focal dermal hypoplasia, coloboma of the iris and eyelids, anal atresia, and extensive limb malformations. When the infant was 3 months old, fibromas started to appear at the fingertips. The cases of three additional patients are described, with a similar combination of multiple digital fibromas, pigmented marks on the temporal region, and limb malformations. One of these patients has consanguineous parents. The clinical findings overlap partially with Gorlin-Goltz syndrome, which has been renamed by some authors "microphthalmia with linear skin defects" (MLS). Since the skin signs are clearly different, however-more like those of Setleis syndrome ("forceps mark" temporal dysplasia)-the patients described here seem to have a new combination of congenital malformations. Deletion of distal Xp, known to occur in some MLS patients, was not detected using cosmids in fluorescence in situ hybridization. This pattern of digital fibroma with congenital malformations seems to represent a new syndrome.- - - - - - - - - - ranking = 1keywords = hybridization (Clic here for more details about this article) |
3/7. Deletion of 2q37 and duplication of 10q24: two cases in the same family and review of the literature.We describe two patients (first cousins, once removed) with an unusual head shape, high arched palate, flat nasal bridge, abnormal ears, hand and feet abnormalities and other anomalies. The patients were ascertained independently and it was initially unknown that they were related to each other. Cytogenetic and fluorescent in situ hybridization (FISH) analysis identified a der(2)t(2;10)(q37.3;q24.1) unbalanced translocation resulting in loss of 2q37.3-qter and duplication 10q24.1-qter. The clinical features of these two patients are compared with previously described cases of 2q deletion and 10q duplication. These patients also emphasize the difficulty in some families of understanding and sharing genetic information and in the difficulties in obtaining an accurate pedigree in a genetics clinic.- - - - - - - - - - ranking = 1keywords = hybridization (Clic here for more details about this article) |
4/7. Terminal tandem duplication of 16p: a case with "pure" partial trisomy (16)(pter-->p13).A new-born infant was found to have multiple congenital anomalies Including bilateral cleft of lip and palate, club-hands and feet, and heart defects. High resolution chromosome analysis showed a de novo tandem duplication of the terminal part of the short arm of chromosome 16, resulting in a dup(16)(pter-->p13). Fluorescent in situ hybridization with a chromosome 16-specific paint confirmed that the extra material belonged to chromosome 16.- - - - - - - - - - ranking = 1keywords = hybridization (Clic here for more details about this article) |
5/7. Duplication 10q confirmed by dna in situ hybridization.Partial duplication of 10q is a recognizable clinical entity. In most of the reported cases, the trisomic segment is identified by a balanced translocation state in a parent. Verification remains a problem in de novo cases. However, the recent availability of whole chromosome probes allows for confirmatory diagnosis of suspected cases. We describe a case of de novo duplication (10q) with verification using dna in situ hybridization.- - - - - - - - - - ranking = 5keywords = hybridization (Clic here for more details about this article) |
6/7. Full monosomy 21, prenatally diagnosed by fluorescent in situ hybridization.We describe a case of full monosomy 21 which was prenatally diagnosed in chorionic villi by fluorescent in situ hybridization (FISH). Because of intrauterine fetal death, a curettage was performed and cytogenetic analysis of skin fibroblasts confirmed the presence of monosomy 21 in fetal cells. dna investigations showed a paternal origin of the single chromosome 21. Inspection and autopsy of the fetus revealed several congenital malformations. Some of them have been reported in earlier studies of monosomy 21; others concern new observations. Regarding the eye, the following abnormalities were microscopically observed: absence of the anterior and posterior eye chambers, aniridy, a hypoplastic ciliary body, Peter's anomaly, and a double retina with secondary dysplasia. In addition, malformations of the extremities were seen: partial, proximal syndactyly of digits 3 and 4 of the right hand; pes varus position of the right foot; and transverse reduction defect at the tarsals of the left foot. To our knowledge, this is the first case in which full monosomy 21 has been proven.- - - - - - - - - - ranking = 5keywords = hybridization (Clic here for more details about this article) |
7/7. Characterization of a supernumerary small marker x chromosome in two females with similar phenotypes.We describe two female patients mosaic for a cell line with an extra marker x chromosome in addition to a normal 46,XX cell line. To our knowledge, these cases are the first reports of females who had a cell line with a supernumerary marker x chromosome in addition to a normal cell line. They also had strikingly similar manifestations, including small hands and feet, minor facial anomalies, obesity, and mental retardation. The dna content of the mar(X) chromosomes was investigated by fluorescent in situ hybridization using pericentromeric probes. The XIST gene, which is necessary for initiation of X-inactivation, was deleted from both marker chromosomes, suggesting that these chromosomes were not subject to inactivation. The short arm breakpoints of the mar(X)s were between the dna markers DXS423E on Xp11.21 and UBE1 on Xp11.23. In Patient 1, mar(X) contained the androgen receptor gene and the dna marker DXS1, both mapping to Xq11.2, whereas in Patient 2 the chromosome breakpoint was proximal to these markers. We suggest that the similar phenotypes of these patients may be due to the overexpression of genes in the common pericentromeric region of the x chromosome.- - - - - - - - - - ranking = 1keywords = hybridization (Clic here for more details about this article) |