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OBJECTIVE: Whereas measurement of albumin:creatinine ratio (ACR) in spot urine samples is indicated for determining microalbuminuria, its performance or that of urinary albumin excretion rate (UAER) in predicting microalbuminuria in sickle cell disease (SCD) is unclear. We therefore tested the diagnostic performance of these measures in spot and timed urine samples in predicting a UAER in 24-hour samples. METHODS: Thirty participants with SCD had spot, two-hour and four-hour, followed by 24-hour urine collections for ACR, urinary albumin concentration (UAC) and UAER determinations. Receiver operating characteristic (ROC) curve analyses were performed. RESULTS: The areas under the ROC curves for microalbuminuria were 0.99 (CI: 0.97, 1.00) for ACR and 0.97 (CI: 0.92, 1.00) for UAC in spot urine samples. For ACR, at the cut-point of 4.13 mg/mmol, there was 100% sensitivity and 82.6% specificity, allowing an 86.2% correct classification. At the cut-point of UAC = 20.9 mg/L, there was 100% sensitivity and 73.9% specificity, allowing a 79.3% correct classification. Corresponding areas for microalbuminuria in two-hour timed samples were 0.99 (CI: 0.95, 1.00) for ACR and 0.96 (CI: 0.89, 1.00) for UAER.For ACR, the cut-point was 4.64 mg/mmol with 83.3% sensitivity and 91.3% specificity, allowing an 89.7% correct classification. Similarly for UAER, at the cut-point of 21.8 µg/min, there was 83.3% sensitivity and 91.3% specificity, allowing 89.7% correct classification. CONCLUSIONS: The diagnostic performance of ACR and UAC in a spot as well as ACR and UAER in two-hour timed urine samples in patients with SCD is excellent. Healthcare professionals can confidently utilize these measures in this patient population.

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OBJECTIVES: The aim of this study is to determine the prevalence and clinicopathological correlates of penile cancer as well as the clinical outcomes in a sample of Jamaicans managed at the University Hospital of the West Indies (UHWI). METHODS: All available records of patients diagnosed with penile cancer from 1998-2008 at the UHWI were obtained. Patient demographics, circumcision status, sexually transmitted infection status, lesion duration, location and size, and lymph node status were obtained. Histology, differentiation and stage were recorded. Information was obtained regarding treatment and outcome. The current data were compared with a previous report from UHWI in 1959. RESULTS: The records of 22 of 26 patients with penile cancer were available for review. Mean (SD) age of patients was 68 (13) years. Eighteen (86%) patients were uncircumcised Mean tumour size was 5.7 (2.6) cm; 8 (36%) lesions involved the entire penis. Sixteen (73%) lesions had clinically regional disease and 11 (52%) patients had advanced pathological stage. Surgical treatment was performed in 15 (68%) patients. Case fatality was 38%, with median survival following surgical intervention of 38 person-months. The major predictor of death in this series was increasing age (HR = 1.06, 95% CI 0.99, 1.1, p = 0.079). There was an increase in age and clinical stage of the cancer at presentation in the current series; however there was no difference in survival. CONCLUSION: Penile cancer is an uncommon cancer, seen at an advanced stage in Jamaicans. Overall survival is poor and advanced age is a major predictor of death.

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The alleles RHCE*ceBI (RHCE*ce 48C, 712G, 818T, 1132G) and RHCE*ceSM (RHCE*ce 48C, 712G, 818T) encode the low-prevalence Rh antigen STEM. These alleles frequently travel in cis with RHD*DOL. To estimate the frequency of these alleles, we tested a total of more than 700 samples in two populations. Blood samples were obtained from patients with sickle cell disease and from blood donors of African descent. DNA extractions and analyses were performed by standard methods. In the United States, none of 70 patient samples had the RHCE*818 nucleotide change. Two of 220 donors (frequency of 0.009) were heterozygous for RHCE*818C/T (RHCE*ceBI). One of these samples had RHD/RHD*DOL and the other had RHD/RHD*DOL-2. In these 290 samples, no other RHD*DOL alleles were found. In Brazil, 1 of 244 patients with sickle cell disease (frequency of 0.004) and 1 of 171 donors (frequency of 0.006) were heterozygous for RHCE*818C/T (RHCE*ceBI). Testing of more than 500 additional samples from people of African descent, selected because they had a diverse range of common and variant RHCE alleles, did not reveal a sample with RHD*DOL or RHD/RHD*DOL-2 in the absence of RHCE*ce(818T). Although the numbers are small, our study shows that in the United States, the frequency of RHCE*818T is 0.007 (2 in 290 samples) and in Brazil it is 0.004 (2 in 515 samples). The four RHCE*818T alleles were RHCE*ceBI.

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Because of the scarcity of anti-Hy and anti-Jo(a), hemagglutination typing for the Dombrock blood group system antigens, Hy and Jo(a), is not feasible. The molecular bases associated with these antigens have been determined, making it possible to distinguish HY and JO from wild-type DO. This provides a tool to predict the probable phenotype of patients and to screen for antigen-negative donors. PCR-RFLP assays and a microchip assay were used to determine the frequency of HY and JO alleles in donors from Brazil and New York. DNA from random Brazilian donors, 288 by PCR-RFLP and 599 by the bead array method (BeadChip, BioArray Solutions, Warren, NJ), was tested to determine 323G/T (HY+/HY-) and 350C>T (JO+/JO-) single-nucleotide polymorphisms. In New York, 27,226 donors who self-identified as being African American were tested by hemagglutination with anti-Gy(a). Nonreactive and weakly reactive samples were tested by PCR-RFLP for the same alleles as listed above. In Brazil, 30 (3.4%) of the samples were JO/DO and 13 (1.4%) were HY/DO. In New York, of the samples that had HY or JO alleles, 14 were homozygous HY/HY 132 were heterozygous HY/DO, 13 were heterozygous HY/JO, 14 were heterozygous JO/DO, and 3 were homozygous JO/JO. These results show that in donors from Brazil, JO (30 alleles) is more than twice as prevalent as HY (13 alleles), whereas in donors from New York, HY (173 alleles) was more than five times more common than JO (33 alleles).

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The molecular background of variant forms of GYPB is not well studied in Brazilians of African descent. The present study was carried out to determine the molecular bases of the S-s- phenotype and the frequency of GYPB*S silent gene for the S-s+ phenotype in a blood donor population of African Brazilians. In this study, 165 blood samples from African Brazilians (Northeastern Brazil) who phenotyped as S-s- (n = 17) and S-s+ (n = 148) by hemagglutination were selected. Allele-specific (AS)-PCR and PCR-restriction fragment length polymorphism (RFLP) were used to identify the variant forms of GYPB. In 13 of 17 S-s- samples (76.5%), both GYPB were deleted. In 137 of the 148 S-s+ samples (92.6%), the AS-PCR was consistent with the S-s+ phenotype. In 4 of the S-s- samples (23.5%) and 11 of the S-s+ samples (7.4%), the AS-PCR showed the presence of a GYPB*S allele associated with silencing of S. In the 4 donors with the S-s- phenotype, there was homozygosity (or hemizygosity) for the GYP(P2) allele (n = 2), homozygosity (or hemizygosity) for the GYP(NY) allele (n = 1), and heterozygosity for the GYP(P2) and GYP(NY) alleles (n = 1). In the 11 donors with the S-s+ phenotype, there was heterozygosity for GYP(P2) allele (n = 8) and heterozygosity for GYP(NY) allele (n = 3). This study reports for the first time the molecular mechanisms responsible for the S-s- phenotype in a population of African Brazilians and provides new information about the frequency and molecular bases of the GYPB*S silent gene (7.4%) in this population.

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The Consortium for Blood Group Genes is a worldwide organization whose goal is to have a vehicle to interact, establish guidelines, operate a proficiency program, and provide education for laboratories involved in DNA and RNA testing for the prediction of blood group, platelet, and neutrophil antigens.

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BACKGROUND AND OBJECTIVES: The Doa and Dob polymorphisms are associated with three single nucleotide polymorphisms (SNPs) in exon 2 of the DO gene: 378C/T, 624T/C and 793A/G for the DOA and DOB alleles, respectively. The SNPs 350C/T (JO allele) and 323G/T (HY allele) are associated with the Jo(a-) and Hy-negative phenotypes. Recently, two new DO alleles [DOB-SH (378C, 624C, 793G) and DOA-HA (378T, 624T, 793A)] were identified using microarray technology. Although the molecular background of Dombrock alleles is well defined, no studies have been conducted in the Brazilian population. MATERIALS AND METHODS: We employed polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP)-based assays and a microarray assay to determine the frequency of the DO alleles (DOA, DOB, HY1, HY2 and JO) in Brazilians. We tested DNA of 288 Brazilians from three different ethnic groups by PCR-RFLP to determine the 793A/G (DOA/DOB), 323G/T (HY), 350C/T (JO) and 898C/G (HY1/HY2) SNPs. We also tested DNA from 162 blood donors by using the HEA Beadchip assay to determine the 378C/T, 624T/C, 793A/G (DOA/DOB), 350C/T (JO allele) and 323G/T (HY) SNPs. RESULTS: Two novel allele combinations were found in our samples: the DOB allele (793G and 323G) associated with 898G (DOB-WL); and an allele carrying the nucleotides 378C, 624C, 793A and 323G (DOA-SH). We also found the DOB-SH and DOA-HA.alleles recently reported. CONCLUSIONS: Our data demonstrate high heterogeneity of DO alleles in the Brazilian population. Our study also highlights the importance of testing a cohort of different populations to determine DO haplotypes and of establishing reliable genotyping tests for predicting Doa/Dob status.

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BACKGROUND: The deficiency of Rh proteins on red blood cells (RBCs) from individuals of the Rh(null) amorph type are the result of homozygosity for a silent RHCE in cis with a deleted RHD. A novel mutation in RHce was identified in two Caucasian Brazilian girls with the amorph type of Rh(null) who were born to parents who were first cousins. STUDY DESIGN AND METHODS: RBCs from the Rh(null) sisters and from family members were analyzed by serology and flow cytometry with specific antibodies. Genomic DNA and transcripts were tested by polymerase chain reaction and sequence analysis. RESULTS: Rh(null) RBCs were nonreactive with anti-Rh and anti-LW. Molecular analyses showed a deletion of RHD and of one nucleotide (960/963; GGGG-->GGG) in exon 7 of the RHce. This deletion introduced a frameshift after Gly321, a new C-terminal sequence, and a premature stop codon, resulting in a shorter predicted protein with 357 amino acids. CONCLUSION: The detection of a unique RHce transcript indicated that the two sisters were homozygous, whereas the other family members were heterozygous for the mutation. A novel mutation resulting in the amorph Rh(null) with loss of Rh antigen expression is described.

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The GATA box single nucleotide polymorphism (SNP) at position -33 (T>C) in Blacks silences the expression of FY*B in erythrocytes, and the substitution 265 C>T, together with 298 G>A, weakens the Fy(b) antigen (Fy(x)). Individuals with these phenotypes/genotypes who receive Fy(b+) blood are unlikely to be alloimmunized to Fy(b) because, in the presence of 265 T, the Fy(b) antigen is expressed, and in the case of -33 C, other tissues express Duffy protein and probably the Fy(b) antigen. We studied samples from 361 blood donors (182 of African ancestry and 179 of Caucasian ancestry) by haemagglutination and polymerase chain reaction (PCR) restriction fragment length polymorphism (RFLP). Forty Caucasian and 130 donors of African ancestry were serologically Fy(b-); among these, the majority of the donors of African ancestry had FY*B with the GATA SNP, while the majority of Caucasians typing Fy(b-) had FY*B with 265 T/298 A SNPs. Six of the Fy(b-) donors (three Africans and three Caucasians) had both GATA and 265/298 SNPs, and six donors of Caucasian ancestry apparently had a GATA SNP. Samples from two donors - one African and one Caucasian with an unusual MspA1I-RFLP pattern - were sequenced and found to have a novel SNP (145 G>T) co-existent with 265 C>T and 298 G>A SNPs. These findings highlight the importance of establishing the incidence and nature of molecular events that impact on Duffy expression in different populations.

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BACKGROUND AND OBJECTIVES: The blood-group antigens Dia and Dib are carried on erythrocyte band 3 and are defined by a single amino acid substitution at position 854 (Leu for Dia and Pro for Dib). The Band 3-Memphis variant has a point mutation (166A>G) in the SLC4A1 gene, which encodes the amino acid substitution Lys56Glu. Two types of Band 3-Memphis, variants I and II, are distinguished by their susceptibility to covalent labelling with 4,4'-diisothiocyanato-1,2-diphenylethane-2,2'-disulphonic acid (H2DIDS). Memphis II is more readily labelled than Memphis I or normal band 3. It is reported that Memphis II is associated with Dia. In a study designed to determine the frequency of the DI*A/DI*B and 166A>G polymorphisms in different populations in Brazil, we found a new DI*A allele. MATERIALS AND METHODS: We studied DNA samples from 70 Amazonian Indians, 71 individuals of Japanese descent, 93 random Brazilian blood donors and 84 blacks with sickle cell disease. Polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) analyses were performed on all samples, using MspI for DI*A/DI*B (exon 19) and MnlI for 166A>G (exon 4). Exon 4 and exon 19 from four outliers were sequenced. RESULTS: Among Amazonian Indians, DI*A and 166G mutations both had a high frequency (0.57 and 0.54, respectively). In individuals of Japanese descent, these alleles were moderately frequent (0.07 and 0.19, respectively). We identified a new allele with DI*A and 166A (56Lys) in four Amazonian Indians. CONCLUSIONS: Our results revealed that DI*A does not have a strict association with 166G. They also show the relevance of testing a cohort of different populations.

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