PubMed Health⌕ Search

Biomedical subjects

T S Sundareshan

Publications and source records attributed to T S Sundareshan.

At least 37 records · Page 2Linked to original sources
PubMed1990

Segregation of acrocentric chromosome association in familial dicentric Robertsonian translocation t(14p;22p), aneuploidy (trisomy-21) and heteromorphism.

The frequency and types of acrocentric chromosome association were quantitatively analysed in a Down syndrome child with unusual karyotype, 46, XX, -14, -22, t dic (14p;22p), +21, 21S+. Father and 4 sibs were heterozygous carriers for t dic (14p;22p). The variant 21S+ was inherited from the mother. The occurrence of translocation and trisomy in the same individual is extremely rare. Acrocentric chromosome association was analysed in this interesting family to understand the interrelationship of acrocentric chromosome association, Robertsonian translocation and heteromorphism, as possible predisposing factors for nondisjunction. Our findings suggest that acrocentric chromosome association is a heritable and nonrandom phenomenon. Heterozygous carriers for translocations and variants are likely to be at increased risk of nondisjunction. Long term family studies will enable to ascertain the causal-relationship of these factors more precisely.

Chromosomes, Human, Pair 14↗
PubMed1989

Direct duplication of chromosome 1, dir dup(1)(p21.2----p32) in a Bedouin boy with multiple congenital anomalies.

Here we describe a Bedouin boy with a de novo duplication of 1p and multiple congenital anomalies. He had microcephaly, convergent squint, anteverted nostrils, malformed ears, micrognathia, hypoplasia of the terminal phalanges, clinodactyly of 5th fingers, simian creases, left inguinal hernia, cryptorchidism, and severe postnatal growth retardation. Our clinical findings are compared with those of previous reports of duplication involving chromosome 1p.

Abnormalities, Multiple↗
PubMed1989

A new autosomal recessive disorder resembling Weaver syndrome.

Most reported cases of Weaver syndrome are sporadic, and the mode of inheritance is still unclear. We describe two (male and female) sibs born to consanguineous Bedouin parents with manifestations resembling Weaver syndrome. Both sibs had accelerated growth of prenatal onset, hypotonia, psychomotor retardation, excess loose skin, peculiar craniofacial and acral anomalies, dental dysplasia and/or serrated gums, joint laxity, and hoarse low-pitched cry. One of them had an accelerated harmonic skeletal maturation. Differentiating features from Weaver syndrome are discussed, and autosomal recessive inheritance is suggested.

Abnormalities, Multiple↗
PubMed1987

Unilateral true hermaphrodite with 46,XX/46,XY dispermic chimerism.

A 13 year old female presented with ambiguous external genitalia, right inguinal ovotestis, left ovary, apparently normal Mullerian system, and absent Wolffian system. Cultured lymphocytes showed a 46,XX/46,XY karyotype. Histopathology of the gonads confirmed true hermaphroditism. The presence of two genetically different erythrocyte populations was observed. The findings suggested that the patient is a true hermaphrodite dispermic chimera.

Adolescent↗
PubMed1987

Robertsonian translocation t dic (14p;22p) with regular trisomy 21: a possible interchromosomal effect?

Robertsonian translocations occur in about 2.5% of Down syndrome. We report here a Down syndrome with karyotype, 46,XX,-14,-22,+der t dic(14p;22p)pat, +21. Proband's father, two sisters, and a brother are phenotypically normal, heterozygous carriers for dicentric t(14;22). This is the only case of a translocation t(14;22) with regular trisomy 21 in our series of 600 Down syndrome cases investigated. The prevalence of balanced Robertsonian translocations in parents of Down syndrome might be higher if all the parents of trisomy 21 individuals were routinely investigated. The case is of interest in understanding the possibility of interchromosomal effect in the etiology of non-disjunction in Down syndrome.

Child, Preschool↗
PubMed1986

Interstitial deletion of the long arm of chromosome 1 [del(1)(q32q42)].

A severely malformed girl died 7 days after birth and was found to have de novo interstitial deletion of 1q (1q32----1q42). Clinical abnormalities included microcephaly, encephalocele, small eyes with unilateral esotropia, hypertelorism but small prominent nose, highly arched palate, micrognathia, abnormal cry, apparently abnormal low-set ears, short neck with low posterior hair line, narrow shoulders, congenital heart defect, hypoplastic nails, overlap of toes with flat feet, and single umbilical artery.

Abnormalities, Multiple↗
PubMed1986

Klinefelter's syndrome, mosaic 46,XX/46,XY/47,XXY/48,XXXY/48,XXYY: a case report.

A 35-year-old male was investigated for primary infertility. Clinical examination showed an intelligent man with normal facial appearance and moustache and small firm testes. Testicular histopathology revealed marked atrophy of the testes with no spermatogenesis and absence of germ cells. Hormonal profile showed elevated levels of FSH,LH and low levels of testosterone. Chromosome analysis from whole blood culture showed cells with 46,XX/46,XY/47,XXY/48,XXXY/48,XXYY mosaicism. The predominant cell line was 47,XXY (87.86%). 46,XY/47,XXY mosaicism is not uncommon. However, mosaicism of multiple sex chromosome aneuploidy is rarely observed. This is the first report of mosaicism in Klinefelter's syndrome variant with five cell lines.

Adult↗
PubMed1986

Clinical findings in an Arab boy with ring (14)(mos 46,XY,r(14)/45,XY,-14).

A five-month male Arab child with clinical features of ring(14) is reported. He had recurrent seizures and chest infections, microcephaly, elongated face, short palpebral fissures, broad nasal bridge, long philtrum, fish-like mouth with thin lips, micrognathia, low-set ears and retinal pigmentation with yellow-white spots on the maculae. In addition brachydactyly of fingers and toes, hypoplastic scrotum and mental deterioration were present.

Abnormalities, Multiple↗
PubMed1985

Complex chromosomal rearrangement involving chromosomes 11, 13, 14 and 18 resulting in monosomy for 13q32----qter.

A five-year-old boy with speech delay, minor facial abnormalities and borderline psychomotor retardation was found to have a complex de novo double translocation involving four chromosomes resulting in monosomy for the segment 13q32----qter. Chromosomes involved were 11, 13, 14, and 18. The translocation between chromosome 11 and 13 was unbalanced with the loss of the segment 13q32----qter. The second translocation between 14 and 18 was apparently balanced.

Child, Preschool↗
PubMed1983

Interstitial deletion of the long arm of chromosome 2: del(2)(q31q33).

A child with a de novo interstitial deletion, 46,XX,del(2)(q31q33), is described. Clinical features included psychomotor retardation, hypotonia, microcephaly, hypertelorism, downward slanting palpebral fissures, macrostomia, cleft palate, micrognathia, abnormal ears, overlapping fingers, simian creases, and rocker bottom feet.

Abnormalities, Multiple↗
PubMedDate not supplied

Cytogenetics of neuroblastoma: a study using fine needle aspiration cultures.

Neuroblastoma is associated with chromosomal aberrations of 1p and 1q in a majority of cases. Some nonrandom secondary changes were observed in this study. The role of these changes in the development and progression of neuroblastoma is examined. Chromosomal analysis was performed on 33 children with neuroblastoma using fine needle aspiration cultures. Metaphases were observed in 57.5% of cases. 86.6% showed the involvement of chromosome 1. Double minutes and unidentifiable markers was also observed. The most frequent secondary changes included add(4)(q35), add(11)(p13), add(14)(q32), add(16)(q12). add(17)(p13), add(19)(q12) and add(21)(q22). Minority of cases showed deletions and translocations. Ploidy pattern ranged from diploid to hypotetraploid. The present study substantiates aberration of chromosome 1 in the form of deletions, additions, duplications and iso-chromosome with some notable secondary abnormalities.

Adolescent↗