Interstitial deletion of the short arm of chromosome 3 (3p14)

Deletions of 3p usually involve the terminal portion (3p25). An interstitial deletion of a proximal 3p segment (3p14) was detected at amniocentesis. The clinical and cytogenetic characteristics of this case and of three previously published cases are reviewed. Cardiovascular and gastrointestinal malformations have not been reported before in association with this particular chromosome abnormality.     

"Tandem" duplication of 4p16.1p16.3 chromosome region associated with 4p16.3pter molecular deletion resulting in Wolf-Hirschhorn syndrome phenotype

Chromosome imbalance affecting the short arm of chromosome 4 results in a variety of distinct clinical conditions. Most of them share a number of manifestations, such as mental retardation, microcephaly, pre- and post-natal growth retardation, anteverted and low-set ears, that can be considered as nonspecific signs, generally attributable to gene dosage impairment. On the other hand, more distinctive phenotypic traits correlate with the segmental aneuploidy. Duplications of the distal half of 4p give rise to the partial trisomy 4 syndrome, characterized by a "boxer" nose configuration and deep-set eyes. These signs are usually observed even in cases of small terminal duplications. Haploinsufficiency of 4p16.3 results in the so-called Wolf-Hirschhorn (WH) syndrome, a contiguous gene syndrome characterized by maxillary hypoplasia, large and protruding eyes, high nasal bridge, skeletal abnormalities, and midline defects. The smallest overlapping deletion described so far as a cause of this condition is only 165 kb long, suggesting that one or a few genes in this region act as "master" regulators of different developmental pathways. A "tandem" duplication of 4p16.1p16.3 was detected in association with a subtle deletion of 4p16.3pter on the same chromosome in a patient with the WH phenotype. The 3.2 Mb deletion, spanning the genomic region from the vicinity of D4S43 to the telomere, encompasses the recently delimited "WHS critical region" [Wright et al., 1997: Hum. Mol. Genet. 6:317-324]. This unusual chromosome rearrangement resulted in WH phenotype, clinical manifestations of partial 4p trisomy being mild or absent. This observation led us to speculate that the regulatory gene/genes in the critical WH region affect the expression of other genes in a dose-dependent manner. Haploinsufficiency of this region could be more deleterious than various partial trisomies.     

Clinical phenotype and molecular analysis of a three-generation family with an interstitial deletion of the short arm of chromosome 5

We report on a 3-generation family with an interstitial deletion of the short arm of chromosome 5. Varied manifestations were found among the affected individuals including microcephaly, hypertonia, and micrognathia; mental retardation was common to all affected individuals. High resolution chromosome analysis was interpreted as del(5) (pter->p14.3::p13.3->qter). Molecular comparison of the deletion in this family with individuals with other 5p deletions suggests that the clinical findings are due specifically to the chromosomal material deleted from 5p13. © Wiley-Liss, Inc.     

Interstitial deletion of the short arm of chromosome 4.

A 17 year old girl investigated for mental retardation and minor anomalies was found to have an interstitial deletion of 4p. Her clinical and cytogenetic findings are compared with previous reported case of interstitial 4p deletion and with terminal 4p--deletions (Wolf-Hirschhorn syndrome).     

A patient with an interstitial deletion of the short arm of chromosome 6

The clinical history and subsequent progress of a child with an interstitial deletion in the short arm of chromosome 6 is described. This abnormality coupled with a reduced Hageman factor (Factor XII) led to an earlier publication which suggested that this gene was localized to the breakpoint region involved. A review of similar phenotypes from the literature is presented.     

De novo direct tandem duplication of the short arm of chromosome 7(p21.1-p14.2)

We report on a 6-year-old boy with moderate developmental retardation and unusual dermatoglyphics. Cytogenetic analysis demonstrated a duplication of chromosome sub-region 7p21.2-p14.2. Confirmation of the specific duplicated region was determined by quantitative Southern blotting by using a DNA fragment previously localized to the portion of chromosome 7 thought to be duplicated. This patient did not have the internal malformations seen with other dup(7p) patients.     

Terminal deletion of chromosome 4p (4p16.3) shows a breakpoint between loci linked to Huntington disease

A 15-year-old boy with a terminal deletion of the short arm of chromosome 4 is described. The patient has a mild clinical phenotype that is incompatible with Wolf-Hirschhorn syndrome. Careful neurological examination including CT scan did not show any signs of Huntington disease. The chromosomal breakpoint was analyzed by means of polymorphic DNA probes localized close to the tentative Huntington (HD) locus. The breakage has occurred between D4S43 and D4S90 loci and thus deletes part of the chromosomal candidate regions for the HD locus. © 1992 Wiley-Liss, Inc.     

Clinical phenotype and molecular analysis of a three-generation family with an interstitial deletion of the short arm of chromosome 5.

We report on a 3-generation family with an interstitial deletion of the short arm of chromosome 5. Varied manifestations were found among the affected individuals including microcephaly, hypertonia, and micrognathia; mental retardation was common to all affected individuals. High resolution chromosome analysis was interpreted as del(5) (pter- > p14.3::p13.3- > qter). Molecular comparison of the deletion in this family with individuals with other 5p deletions suggests that the clinical findings are due specifically to the chromosomal material deleted from 5p13.     

A new cytogenetic subgroup in uterine leiomyoma is characterized by a deletion of the long arm of chromosome 3

Our cytogenetic findings in 175 uterine leiomyomas revealed 52 tumors with clonal chromosome abnormalities, eight of which did not belong to any well-delineated cytogenetic abnormal subgroup. However, an interstitial deletion of the long arm of chromosome 3 was found, as the sole chromosome abnormality, in three cases. We believe that this involvement of 3q is significant enough to consider it as a new cytogenetic subgroup of uterine leiomyoma. © 1995 Wiley-Liss, Inc.     

Interstitial deletion of the short arm of chromosome 1 (46XY), del(1)(p13p22.3)

A male patient with a de novo proximal interstitial deletion of the short arm of chromosome 1 (46XY), del(1)(p13p22.3) is described with multiple anomalies and developmental delay. This patient's clinical manifestations are compared to previously reported patients with deletions of chromosome 1p.© 1992 Wiley-Liss, Inc.     

Terminal deletion of the short arm of chromosome 5

Three cases of deletion of the short arm of chromosome 5 are described: one family cluster, in which the mother and three sons are affected, and two sporadics without the typical "cri du chat" phenotype (the family and Case 2 were previously reported in 1982). Mental retardation varied between affected members of the same family. Band p15.2 appears critical for the development of the complete phenotype. A peculiar deafness observed in the familial and one of the sporadic cases suggests a cochlear malformation.     

Distal deletion of the short arm of chromosome 6

We report on a patient with deficiency of distal 6p and compare the clinical and cytogenetic findings in this child with those of three previously reported patients who had similar deletions. Distal del(6p) appears to be associated with a relatively non-specific phenotype, with the possible exception of unusual congenital eye findings. This apparent association of congenital eye defects with distal del(6p) was supported by comparison with patients having other deletions of chromosome 6, particularly those with ring chromosome 6.     

Terminal deletion of the short arm of chromosome 3

Summary A boy with growth and mental retardation, flat occiput, high and broad forehead, blepharoptosis, narrow palpebral fissures, low set, malformed ears, short neck, anal atresia, deep sacral dimple is reported. High-resolution banding analysis showed terminal deletion of the short arm of chromosome 3 (46,XY,del(3)(p25.3)). Deletions of the short arm of chromosome 3 are relatively rare. The clinical features of the patient are compared with those of 19 previously reported cases.     

An interstitial deletion of the long arm of chromosome 13

A case of an interstitial deletion of chromosome 13, identified as 46,XY,del(13)(q22q31), is reported in a child with psychomotor retardation, prominent low-set ears, epicanthus, hypertelorism, broad nasal bridge, hypoplastic fifth fingers and abnormal dermatoglyphics. This patient is compared to others in the literature with a similar deletion.