Aniridia: enzyme studies in an 11p--chromosomal deletion.

A patient with aniridia and an interstitial deletion of the bands p13-p14 of the short arm of chromosome 11 was studied to determine the relative locations of the gene(s) encoding for the aniridia-Wilms' tumor association with other genes on the same chromosome. Quantitative analysis was performed on the red blood cell enzymes lactic acid dehydrogenase-A (LDH-A) and catalase, the genes for which are located on the short arm of chromosome 11. The activity of LDH-A was normal; the activity of catalase was reduced to approximately half normal.

Location of the retinoblastoma susceptibility gene(s) and the human esterase D locus.

Retinoblastoma occurs with increased frequency in children born with a deletion of the long arm of chromosome 13. Recent reviews have noted that the region 13q14 is consistently deleted in documented cases. Prometaphase and late prophase banding allowed Yunis and Ramsay to determine that a deletion in one patient included the sub-bands q14 .

Trisomy 18 phenotype in a patient with an isopseudodicentric 18 chromosome.

We report a female patient with a typical trisomy 18 phenotype who has a 46,XX, -18, +isopseudodic(18)(p11) karotype. The lack of features of the 18p- syndrome suggests that a significant amount of short arm material is present and that the Turner-like features associated with 18p- may be determined by monosomy for 18p11. The phenotype-genotype correlations in abnormalities affecting chromosome 18 are reviewed.

Bone marrow transplantation from identical twins in the treatment of aplastic anaemia: implication for the pathogenesis of the disease.

Treatment of aplastic anaemia by bone marrow transplantation from a syngeneic (identical twin) donor has provided insights into the pathophysiology of the disease. We report from patients with severe anaemia who were treated by syngeneic bone marrow transplantation. None of the patients had sustained recovery of peripheral blood counts.

Genetic linkage studies of transferrin, pseudocholinesterase, and chromosome 1 loci.

Genetic linkage analysis of a pedigree with four different alleles for pseudocholinesterase (CHE1) gives a positive lod score of 0.37 at theta = 0.16 for linkage with transferrin (TF), a finding which supports previous reports of linkage between CHE1 and TF.

Estimating the recombination frequency for the PTC-Kell linkage.

Two data sets are analyzed for linkage between the PTC and Kell blood group loci. The original report of close linkage for these loci was that of Conneally et al. (1976), where the maximum likelihood estimate of theta was 0.

Peters' anomaly associated with partial deletion of the long arm of chromosome 11.

A 5-week-old boy with Peters' anomaly was found to have an interstitial deletion of the long arm of chromosome 11; no developmental delays or dysmorphic features were evident. His right cornea was enlarged and opaque with extensive pannus formation; the anterior chamber, iris, and lens were not visible. The left eye showed a central opacity and a superficial pannus; the optic disk and macula could not be visualized.

Regional localization of the human genes for S-adenosylhomocysteine hydrolase (cen----q131) and adenosine deaminase (q131----qter) on chromosome 20.

The gene loci for S-adenosylhomocysteine hydrolase ( AHCY ) and adenosine deaminase (ADA), two enzymes with related metabolic functions, have both been assigned to human chromosome 20. We have used rodent-human somatic hybrids containing translocations involving human chromosome 20 to more precisely determine the relative locations of the AHCY and ADA loci. Our results assign the AHCY locus to the long arm of chromosome 20, in the region cen---- q131 , and ADA to the region q131 ----qter.

Separation of retinoblastoma and esterase D loci in a patient with sporadic retinoblastoma and del(13)(q14.1q22.3).

A chromosome 13 deletion in a patient with sporadic retinoblastoma appears to have separated the loci for retinoblastoma and esterase D. This study indicates that: (1) the retinoblastoma locus is distinct from the esterase D locus; and (2) the linear order of these genes is centromere-esterase D-retinoblastoma.

Evidence of autonomous red cell expression of Xga antigen in human bone marrow transplantation.

Human bone marrow transplant chimeras afford the opportunity to determine whether a red blood cell antigen is autonomously controlled. Evaluation of an Xg(a-) recipient and an Xg(a+) recipient, each transplanted with bone marrow of donors of opposite Xga types, shows that the Xga antigen is of the donor type following transplantation. This indicates that the Xga antigen is controlled by the red blood cell, and confirms earlier studies in natural chimeras.

Transferase-deficiency galactosemia: immunochemical studies of the Duarte and Los Angeles variants.

Rabbit antibodies to purified human placental galactose-1-phosphate uridyltransferase (EC 2.7.7.

Y chromosome length related to fetal loss.

The Y/20 ratio (length of Y chromosome/length of chromosome 20) was examined among 216 males, 108 of whose wives had a history of repeated abortions (study group), and 108 who were mentally retarded (controls). There was no significant difference in frequency of long Y (Y/20 equal to or greater than 1) between the study group and controls. Also, there was the expected male: female ratio among normal living children of couples in the study group, and the Y/20 ratio was not significantly increased among fathers with abnormal male offspring.

The search for heterogeneity in insulin-dependent diabetes mellitus (IDDM): linkage studies, two-locus models, and genetic heterogeneity.

One hundred families with insulin-dependent diabetes mellitus (IDDM) were analyzed for linkage with 27 genetic markers, including HLA, properdin factor B (BF), and glyoxalase 1(GLO) on chromosome 6, and Kidd blood group (Jk) on chromosome 2. The linkage analyses were performed under several different genetic models. An approximate correction for two-locus linkage analysis was developed and applied to four markers.

Linkage analysis of neurofibromatosis (von Recklinghausen disease).

Linkage analysis of 28 genetic markers was undertaken in 108 subjects from 11 families with well-documented, classic, peripheral neurofibromatosis. Fifty-four persons were affected in one four-generation family, seven three-generation families, and three two-generation families. Lod scores were calculated using the standard LIPED programme for 49 combinations of theta male and theta female from 0.

Association studies between Type 1 (insulin-dependent) diabetes and 27 genetic markers: lack of association between Type 1 diabetes and Kidd blood group.

One hundred and three unrelated patients with Type 1 (insulin-dependent) diabetes were typed for HLA, properdin factor B (BF), glyoxalase 1 (GLO), Kidd blood group, and 24 other genetic markers. Observed distributions of marker phenotypes among these patients were compared with those expected according to population frequencies, in an attempt to detect associations between Type 1 diabetes and the markers. Strong associations between Type 1 diabetes and both HLA and properdin factor B were confirmed, as was a lack of association between Type 1 diabetes and glyoxalase (GLO).

Segregation and linkage analyses in families of patients with bipolar, unipolar, and schizoaffective mood disorders.

Hypotheses of single major locus transmission (autosomal and X chromosome) of major affective disorder (i.e., bipolar, unipolar, and schizoaffective) are tested using the Elston-Stewart likelihood method of pedigree segregation analysis.

Chromosomal abnormalities of a mediastinal embryonal cell carcinoma in a patient with 47,XXY Klinefelter syndrome: evidence for the premeiotic origin of a germ cell tumor.

Trypsin-Giemsa banding studies were performed on 30 tumor cells from an embryonal cell carcinoma originating in the mediastinum of an 18-year-old male with the Klinefelter syndrome (47,XXY). All tumor cells revealed an XXY chromosomal pattern with the addition of extra chromosomes. Electrophoretic patterns of the patient's red blood cells and tumor cells were identical.

Gene for hereditary retinoblastoma assigned to human chromosome 13 by linkage to esterase D.

Evaluation of three families with hereditary retinoblastoma demonstrates close linkage of the gene for this tumor with the genetic locus for esterase D. These results assign the gene for the hereditary form of retinoblastoma to band q14 on chromosome 13, the same region which is affected in the chromosome deletion form of this eye tumor, and therefore suggest a common underlying mechanism in the pathogenesis of these two forms of retinoblastoma.

Patient with 13 chromosome deletion: evidence that the retinoblastoma gene is a recessive cancer gene.

Although a constitutional chromosomal deletion including 13q14 has been found to date in all retinoblastoma patients whose esterase D activity is 50 percent of normal, one female patient has been found who has 50 percent esterase D activity in all normal cells examined but no deletion of 13q14 at the 550-band level. Therefore, she has the smallest constitutional chromosomal deletion within 13q14 that is associated with susceptibility to retinoblastoma. Two stem lines were identified in a retinoblastoma from this patient, and each one had a missing 13 chromosome.

Normal superoxide dismutase-1 (SOD-1) activity with deletion of chromosome band 21q21 supports localization of SOD-1 locus to 21q22.

The gene for superoxide dismutase-1 (SOD-1) is clearly on chromosome 21, although there is disagreement on the precise band location of SOD-1 on the long (q) arm of number 21. We report a patient with normal superoxide dismutase-1 (SOD-1) activity and an interstitial deletion of chromosome 21 resulting in monosomy for band q21. His phenotype is characterized by moderate mental retardation, a long narrow face, high and arched palate, cardiac murmur, undescended testes, and long hyperflexible extremities.

Glyoxalase I "null" allele in a new family: identification by abnormal segregation pattern and quantitative assay.

A GLO-I "null" allele in a family was indicated by an abnormal segregation pattern and by half normal red cell enzyme activity in carriers. This is the third reported instance of this uncommon allele, and the first with confirmation by quantitation of enzyme activity.

High resolution chromosome banding in the Rubinstein-Taybi syndrome.

We studied eight cases of the Rubinstein-Taybi syndrome to determine if a detectable chromosome change is associated with this syndrome. High resolution G-banded analysis of prometaphase chromosomes was carried out on venous blood with two to four karyotypes analyzed for each patient. Initial study of two patients suggested an abnormality in chromosome 15q, but blinded analysis and review of the karyotypes proved to be normal.

Glutamate pyruvate transaminase null allele in seven new families.

Based upon aberrant segregation of glutamate pyruvate-transaminase (GPT) and reduced enzyme activity on electrophoresis, seven new families with a GPT null allele were identified during genetic linkage analysis for a number of different traits.