Objective To make molecular diagnosis for puerile spinal muscular atrophy(SMA).Methods Genomic DNA was extracted directly from the blood of both the case group(10 children with SMA) and the control group(including 19 parents of SMA patients and 20 healthy individuals).Two methods,polymerase chain reaction-restriction fragment length polymorphism(PCR-RFLP) and allele-specific PCR,were used to analyze exon 7 of SMN gene from genomic DNA,and consequent electrophoresis of PCR products on agarose gel was performed.Results Genotyping results obtained by both methods were in complete agreement for all of the samples analyzed.In conventional PCR-RFLP,part of the PCR products(189bp) from genomic DNA of all 39 members in the control group remained intact after digestion with Dra I,while the PCR products from genomic DNA of all 10 SMA children in the case group was completely digested by Dra I.In allele-specific PCR,exon 7 of both SMN1 and SMN2 could be seen when genomic DNA of all 39 members in the control group was used,while only SMN2's exon 7 could be seen when genomic DNA of all 10 SMA children in the case group was used.Conclusion Homozygous deletion of SMN1 was present in all 10 SMA children in the case group,while homozygous deletion of SMN1 was not detected in all 39 members in the control group.The combination of PCR-RFLP and allele-specific PCR,both their results can be references for each other,offers efficient and accurate methodology for molecular diagnosis of SMA.

T),one dinucleotide deletion(1801-02 del AG) and one base insertion(1125 ins GCCATCG),which resulted in eight missense mutations,two nonsense mutations and two frame shift mutations,namely P534R,G343V,R259W,A141T,R401Q,K276E,Y174C,A314P,S108X,Q177X,fs E471 and fs A247.Conclusion The combined DHPLC and sequencing approach may act as a rapid and efficient method for ABCD1 gene mutation analysis in patients and carriers of X-linked adrenoleukodystrophy families.There exist different ABCD1 gene mutations in different pedigrees,and no obvious correlation between the genotype and phenotype has been found.

Objective To investigate methods for prenatal molecular diagnosis of fetuses at high risk for X-linked adrenoleukodystrophy(X-ALD).Methods The amniotic fluid was obtained and genomic DNA was isolated from amniotic fluid cells.Maternal contamination was evaluated by paternity test.PCRRFLP,sequencing and denaturing high performance liquid chromatography(DHPLC)were used to detect the ABCD1 gene of fetal genome.Results In the pedigree 1,the PCR product(799 bp)of the fetus 1 and her father(normal control)could be digested with BcnI. No P560L mutation,which was present in the index patient,was detected in the ABCD1 gene from the genomic DNA of the fetus 1 using direct sequencing.In the pedigree 2,the PCR product(232 bp)of the fetus 2 and her father could not be digested with MaeI and no Q177X mutation,which was present in the propositus,was detected in the ABCD1 gene from the genomic DNA of the fetus 2 using direct sequencing.In the pedigree 3,the PCR product(271 bp)was digested with AciI.the pattern of the fetus 3 and the propositus being the same,and the R617C mutation was found in the ABCD1 gene from the genomic DNA of the fetus 3 using direct sequencing.In the pedigree 4,the PCR product(269 bp)was analyzed with the DHPLC,and the pattern of elution peaks of the fetus 4 and her father was similar,but different from that of the propositus.No K276E mutation was detectable in the ABCD1 gene from the genomic DNA of the fetus 4 by using direct sequencing.Judging from the sex of the fetuses,fetuses 1 and 2 were normal homozygotes,fetus 3 was an ALD hemizygote,and fetus 4 was a normal hemizygote.Conclusion A new protocol for X-ALD prenatal molecular diagnosis is proposed,which would ensure the accuracy of prenatal diagnosis.

Objective:To seek the optimal melanin-removal method for hematoxylin and eosin (HE) staining, immunohistochemistry and molecular detection.Methods:Thirty-eight paraffin tissue samples of malignant melanoma diagnosed at the Fujian Cancer Hospital, Fuzhou, China between January 2018 and March 2022 were collected and used to make a tissue microarray. Melanin in these cases was removed using warm hydrogen peroxide, double oxidation depigmentation, modified potassium permanganate-oxalic acid or trichloroisocyanuric acid, followed by HE staining. The cases were divided into two cohorts: one was subject to the one of the above four methods to remove melanin first, followed by immunohistochemistry (SOX-10, Ki-67, HMB45 and Melan A), while the other was subject to immunohistochemical staining first and then a melanin removal. Following that, seventeen melanin-rich paraffin tissue samples were collected and depigmented using the methods described above. DNA extraction was then done, followed by assessments of DNA content and quality. Moreover, the completeness of melanin removal, the effect on HE and immunohistochemical staining, and the quality of DNA were compared between the depigmented methods.Results:Regarding the effectiveness of melanin removal, the modified potassium permanganate-oxalic acid and the warm hydrogen peroxide methods were the most effective, and both showed residual melanin in only 5.26% (2/38) of the cases. The trichloroisocyanuric acid method showed residual melanin in 10.53% (4/38) of the cases. The worst was the double oxidation depigmentation method, which showed pigment residue in 15.79% (6/38) of the cases. For HE staining, the percentage of good staining with the warm hydrogen peroxide method was 92.11%, higher than the other three methods. For immunohistochemical staining, the mean staining scores of immunohistochemistry first followed by melanin removal with modified potassium permanganate-oxalic acid, double oxidation and trichloroisocyanuric acid were 20.84, 26.63 and 35.02, respectively. These immunohistochemical staining scores were higher than those of melanin removal first followed by immunohistochemistry (8.70, 15.41 and 21.22, respectively). The mean staining score of melanin removal by warm hydrogen peroxide method followed by immunohistochemistry was 33.57, superior to that of immunohistochemistry followed by the melanin removal (19.96). Moreover, the staining scores of HMB45, MelanA and Ki-67 with immunohistochemical staining followed by trichloroisocyanuric acid method were 36.45, 33.79, and 36.24, respectively, while the staining score of SOX10 with melanin removal by warm hydrogen peroxide followed by immunohistochemistry was 34.39. The DNA was significantly degraded by modified potassium permanganate-oxalic acid, double oxidation depigmentation and trichloroisocyanuric acid, whereas the mean concentration of DNA extracted after melanin removal by hydrogen peroxide method was 59.59 μg/L, substantially higher than that of DNA extracted without melanin removal (30.3 μg/L, P=0.001). The A260/ A280 of DNA extracted after melanin removal by hydrogen peroxide was between 1.8 and 2.0 in all cases, and the A260/ A230 was above 2.0 in sixteen cases, suggesting high purity of DNA. However, the DNA extracted without removing the melanin showed poor purity, with A260/ A280 below 1.8 in eight cases and A260/ A230 below 2.0 in sixteen cases. Conclusions:Warm hydrogen peroxide showed the least melanin residue, superior HE staining and a minimal effect on DNA purity/quality compared to the other three methods. It thus appears most suitable for PCR, NGS and other molecular detection. Melanin removal with trichloroisocyanuric acid after immunohistochemical staining has the least melanin residual, and thus could be the most convenient and efficient. However, it is noted that the efficacy of the same depigmentation method varies with different antibodies. Therefore, the optimal depigmentation method should be selected based on the specific markers of interest.

Purpose To explore the clinicopathological features,diagnosis and differential diagnosis of large B-cell lym-phoma with IRF4 rearrangement(LBCL-IRF4r).Methods Clinical data of 8 cases of LBCL-IRF4r were collect,hematoxy-lin-eosin and immunohistochemical of EnVision two-step stains,in situ hybridization and FISH was used to study the histology,immunotypes and molecular genetic characteristics.The rele-vant literatures were reviewed.Results Among 8 cases of LBCL-IRF4r,the male to female ratio was 1.67:1,with age range 10-53 years(mean 25.8 years).Five cases occurred in tonsils,2 cases in nasopharynx and 1 cases in inguinal lymph node.Microscopically,the tumors presented with a purely follic-ular,purely diffuse or a combined follicular and diffuse architec-ture.The tumor cells were typical centroblasts and less frequent-ly medium-sized blastic cells with smaller nucleoli,apoptosis and nuclear fragmentation were easily seen.Immunophenotypi-cally,the tumor cells of the eight cases of LBCL-IRF4r diffuse strongly expressed CD20(8/8),PAX5(2/2),CD79a(3/3),BCL6(8/8)and MUM-1(8/8),mostly expressed CD10(7/8),partially expressed BCL2(5/8)and CD5(4/8),and did not express Cyclin D1,CD23 and CD30.The percentage of Ki67 index ranged from 70％to 95％.EBER in situ hybridiza-tion was negative in all cases.IRF4 rearrangements were detec-ted in all cases(8/8).BCL6 rearrangements were detected in one case(1/2).MYC(0/4)and BCL2(0/3)rearrangements were not detected in all cases.Conclusion LBCL-IRF4r is more common in children and adolescents with characteristic IG::IRF4 rearrangement and a good prognosis,which needs to be differentiated from other types of large B-cell lymphoma.