Genomic features of lung cancer patients harboring germline mutations associated with hereditary cancer syndromes.

e20511 Background: Smoking and air pollution are the major causes of lung cancer; however, numerous studies have demonstrated that genetic factors also contribute to the development of lung cancer. Here, we reported an analysis of genomic features in 65 lung cancer patients with autosomal-dominant or autosomal-recessive inheritance of germline mutations. Methods: We retrospectively reviewed next-generation sequencing data of 26,904 lung cancer patients in a Chinese cohort. The germline mutation patterns, as well as the co-occurrence with somatic driver mutations were analyzed. Results: A total of 65 (0.24%) patients with heterozygous germline mutations associated with hereditary cancer syndromes were detected, including 27 (0.10%) patients with autosomal-dominant inheritance (BRCA1, BRCA2, RET and TP53) and 38 (0.14%) patients with autosomal-recessive inheritance (ATM, BLM, FANCA, FANCG, MUTYH, NBN, RECQL4 and WRN). Comparing to patients with autosomal-dominant inheritance (Age 56±17.8), patients with autosomal-recessive inheritance (Age 65±11.7, P = 0.009) were older, and there is no gender difference. Additionally, 66.7% (18/27) of patients with autosomal-dominant inheritance were identified co-mutated actionable variations, such as 12 patients harboring mutations in exon 18–21 of EGFR, 2 patients harboring ERBB2 exon 20 insertions, 3 patients harboring mutations in exon 2 of KRAS and 1 patient harboring EML4-ALK fusion. The coexistence of germline autosomal-dominant mutations and somatic driver mutations indicated that germline mutations have weak impact on lung cancer. Simultaneously, 52.6% (20/38) of patients with autosomal-recessive inheritance were identified co-mutated actionable variations, such as 15 EGFR+ patients, 2 ERBB2+ patients and 3 KRAS+ patients. And there was no significant difference in population frequency of co-mutated actionable variations between the two groups. Conclusions: In summary, studies on germline mutations of lung cancer patients may help to elucidate the etiology and mechanism of lung cancer, and may help for early detection and diagnosis, targeted therapy and improved prevention strategies.

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The combined novel KCNQ1 frameshift I145Sfs*92 and nonsense W392X variants caused Jervell and Lange-Nielsen syndrome in a Chinese infant presenting with sustained foetal bradycardia

EP Europace ◽

10.1093/europace/euaa154 ◽

2020 ◽

Vol 22 (12) ◽

pp. 1880-1884

Author(s):

Yanmin Zhang ◽

Xiaomin Li ◽

Ying Yang ◽

Jie Wang ◽

Xinru Gao ◽

...

Keyword(s):

Autosomal Recessive ◽

Autosomal Dominant ◽

Autosomal Recessive Inheritance ◽

Autosomal Dominant Inheritance ◽

Incomplete Penetrance ◽

Recessive Inheritance ◽

Dominant Inheritance ◽

Heterozygous Variant ◽

Bilateral Sensorineural Hearing Loss ◽

Electrocardiogram Ecg

Abstract Aims We report clinical and molecular analysis of an infant presenting with foetal bradycardia and clinical outcome of Jervell and Lange-Nielsen syndrome (JLNS). Methods and results Clinical, electrocardiogram (ECG), and echocardiographic data were collected from members in a three-generation family. Whole exomes were amplified and sequenced for proband. The identified variants were verified in the remaining members. The pathogenicity of candidate variants was predicted using multiple software programmes. A 28-year-old non-consanguineous Chinese woman at 23 weeks’ gestation presenting with sustained foetal bradycardia of 100 b.p.m. Immunological disorders and infection were excluded. The infant was delivered at 37 weeks’ gestation with 2700-g birthweight. QTc was prolonged in both ECG and Holter recording. Hearing tests confirmed bilateral sensorineural hearing loss. Genetic testing demonstrated that the infant carried a novel frameshift c.431delC (p.I145Sfs*92) and a novel nonsense c.1175G>A (p.W392X) compound variants of KCNQ1 inherited from mother and father, respectively, in autosomal recessive inheritance. Only relative II-5 carrying heterozygous KCNQ1-I145Sfs*92 variant had prolonged QTc, while the other carriers did not have prolonged QT, suggesting an autosomal dominant inheritance of LQT1 phenotype with incomplete penetrance in the family. Conclusion We report the novel frameshift KCNQ1-I145Sfs*92 and nonsense KCNQ1-W392X compound variants in autosomal recessive inheritance that caused JLNS presenting as sustained foetal bradycardia for the first time. Meanwhile, KCNQ1-I145Sfs*92 heterozygous variant demonstrated LQT1 phenotype in autosomal dominant inheritance with incomplete penetrance.

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Genetic hearing loss: a study of 228 Brazilian patients

Genetics and Molecular Biology ◽

10.1590/s1415-47572000000100004 ◽

2000 ◽

Vol 23 (1) ◽

pp. 25-27 ◽

Cited By ~ 3

Author(s):

Silvia Bragagnolo Longhitano ◽

Décio Brunoni

Keyword(s):

Hearing Loss ◽

Autosomal Recessive ◽

Autosomal Dominant ◽

Autosomal Recessive Inheritance ◽

Recessive Inheritance ◽

Dominant Inheritance ◽

Genetic Etiology ◽

Parental Consanguinity ◽

Genetic Hearing Loss ◽

Associated Abnormalities

We studied 228 patients, with suspected or confirmed genetic hearing loss, in order to determine the clinical and genetic diagnoses and etiology of each case. Deafness with no associated abnormalities was found in 146 patients (64%) belonging to 112 families. Syndromic deafness was diagnosed in 82 patients (36%) belonging to 76 families. The genetic etiology was as follows: autosomal recessive inheritance in 40.8% of syndromics and non-syndromics, autosomal dominant inheritance in 13.2% and X-linked recessive in 1.3%. In 44.7% of the cases, the etiology of the hearing loss could not be determined. Monogenic causes are the most possible etiology in the latter cases. Parental consanguinity was found in 22.4% of the cases, and deafness was bilateral, profound and neurosensorial in 47.4% of the patients. An early onset of hearing loss (< 2 years of age) occurred in 46.5% of the cases. These results are similar to previous literature reports.

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Congenital Aspirin-like Defect As a Result of Autosomal Recessive Variants in PTGS1

Blood ◽

10.1182/blood-2018-99-118958 ◽

2018 ◽

Vol 132 (Supplement 1) ◽

pp. 1156-1156

Author(s):

Suthesh Sivapalaratnam ◽

Hayman Melissa ◽

Claire Lentaigne ◽

Melissa Chan ◽

Marilena Crescente ◽

...

Keyword(s):

Arachidonic Acid ◽

Platelet Aggregation ◽

Platelet Function ◽

Autosomal Recessive ◽

Autosomal Dominant ◽

Autosomal Recessive Inheritance ◽

Recessive Inheritance ◽

Dominant Inheritance ◽

Platelet Function Disorders ◽

First Time

Abstract Inherited defects of platelet function disorders are rare and difficult to diagnose due to lack of standardized platelet tests. An aspirin-like platelet defect is characterised by reduced thromboxane A2 (TXA2) signalling due to a defect in the arachidonic acid (AA) pathway in platelets. Patients with aspirin-like defect present with mild to moderate bleeding symptoms and impaired platelet aggregation responses to AA and ADP. This is similar to the irreversible effect of aspirin on platelets, which is mediated through inhibition of prostaglandin H synthase-1 also known as cyclooxygenase-1 (PTGS1/COX1). We for the first time report platelet function disorders due to autosomal recessive inheritance of variants in PTGS1. In a total of 3563 cases with bleeding disorders, comprising 1169 whole genome sequenced probands of the BRIDGE-BPD study and 2394 panel sequenced index cases of the ThromboGenomics cohort, we identified 15 unrelated cases of each cohort with an aspirin-like platelet function defect. Two of these cases had rare a variants in PTGS1, the gene encoding COX-1, which catalyses the conversion of arachidonic acid to prostaglandin H2. The first case presented with epistaxis and peri-operative bleeding. She had reduced platelet aggregation responses to arachidonic acid, ADP, collagen and epinephrine. Incubation of control blood with collagen resulted in enhanced levels of thromboxane B2, PGD2, PGE2, 11-HETE and 15-HETE which was absent in the index case.We identified a homozygous missense variant in PTGS1, p.Trp322Ser with a Combined Annotation Dependant Depletion Score (CADD) of 31.0. This variant was absent from GnomAD. The variant co-segregated in an autosomal recessive inheritance mode, with aspirin-like defect phenotype in the seven family members who were investigated. PTGS1 was not expressed on the platelets by western blot. Immunophenotyping demonstrated absence on the platelet surface but presence on neutrophils. The second case of the presented with menorrhagia, nosebleeds, easy bleeding and bruising. She had reduced aggregation responses to arachidonic acid, ADP, collagen and epinephrine. We identified two variants in cis: a splice-donor variant (g. 125133553 T>A), CADD 24.3; and an upstream non-coding variant (g. 125132069 C>G), CADD 16.63. The frequency of these variants were respectively; 1.7 x 10-5 and 8 x 10-3 in GnomAD. Platelet RNA and protein expression studies in the propositus revealed alternative splicing with the generation of a smaller protein due the splice variant. In contrast, the non coding variant had no effect on promoter or enhancer activity and therefore, is likely benign. In this case, the mode of inheritance is autosomal dominant with a dominant negative effect, which has been reported previously. For the other 13 cases of the Bridge-BPD study we also interrogated the non-coding space and interactors in the arachidonic acid pathway, none of which had genetic variants explaining the phenotype. For the 15 ThromboGenomics cohort cases because they were sequenced on targeted platform similar investigations could not take place. These cases could have a non inherited cause for the platelet defect or it is also permissible that variation in a hitherto undefined pathways unique to individual cases might be causal. In conclusion, we for the first time report autosomal recessive inheritance of variants in PTGS1 as cause for a rare inherited bleeding disorder. The effect of the mutation are selective loss of expression of PTGS1 within platelets and decreased enzyme function. Two previous reports demonstrated autosomal dominant inheritance. The first demonstrated autosomal dominant inheritance of variants in PTGS1 as modifier in a well characterized family with haemophilia A and platelet function disorder (Nance et al JTH 2016). The second reported rare heterozygous variants in PTGS1 in two cases with a bleeding tendency which was not further specified in the report (Bastida et al Haematologica 2018). Disclosures Laffan: Pfizer: Honoraria; Roche: Consultancy, Speakers Bureau.

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FAMILIAL SELECTIVE IgA DEFICIENCY

PEDIATRICS ◽

10.1542/peds.49.1.71 ◽

1972 ◽

Vol 49 (1) ◽

pp. 71-79

Author(s):

Patricia A. Nell ◽

Arthur J. Ammann ◽

Richard Hong ◽

E. Richard Stiehm

Keyword(s):

Antibody Production ◽

Autosomal Recessive ◽

Autosomal Dominant ◽

Autosomal Recessive Inheritance ◽

Iga Deficiency ◽

Recessive Inheritance ◽

Dominant Inheritance ◽

Selective Iga Deficiency ◽

Immunoglobulin Synthesis ◽

Autoantibody Formation

Thirteen subjects with selective IgA deficiency were obtained from five separate families. In three families an autosomal recessive inheritance was apparent while an autosomal dominant inheritance appeared very likely in the two remaining families. An increased incidence of quantitative defects in immunoglobulin synthesis was seen in addition to evidence of abnormal antibody production and increased autoantibody formation.

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