miRBase entry: hsa-let-7a-1

Stem-loop hsa-let-7a-1

Homo sapiens hsa-let-7a-1 precursor miRNA
Gene family
MIPF0000002; let-7

Caution, this is an AI generated summary based on literature. This may have errors. ?

MIRLET7A1 is a microRNA gene located on chromosome 9q22.3 [PMC5356719]. It is one of the three genes expressing let-7a, along with MIRLET7A2 on 11q24.1 and MIRLET7A3 on 22q13.3 [PMC5356719]. MIRLET7A1 has been studied in the context of adenoviral shuttle vectors and priMIR expression vectors [PMC6923634]. It is targeted by several miRNAs, including members of the let-7 family, suggesting potential auto-regulation [PMC7961530]. MIRLET7A1 has also been included in targeted capture assays for detecting structural variations and copy number analysis [PMC7815088]. In the context of acute lymphoblastic leukemia (ALL), variants in MIRLET7A1 have been associated with severe hematologic toxicity arising from treatment [PMC10003057]. Specifically, variants rs12904 (MIR200C), rs3746444 (MIR499A), and rs10739971 (MIRLET7A1) have shown significant associations with hematologic toxicity in ALL patients [PMC10003057]. Furthermore, the rs10739971 variant of MIRLET7A1 has been associated with a potential protective factor against toxic hematological events in pediatric patients undergoing ALL treatment [PMC10003057]. However, no significant differences have been found for genotype and allele frequencies of several miRNAs including MIRLET7A1 between cases and controls in a specific population studied for breast cancer susceptibility [PMC4650490]. Chromosomal loss at 9q22 has also led to recurrent loss of the MIRLET7A gene family, including MIRLET7A1 [PMC7459851]. Overall, studies suggest that MIRLET7A1 plays regulatory roles in cellular processes and may have implications in cancer and therapeutic response [PMC8840188] [PMC10003057] [PMC7459851].

Literature search
1270 open access papers mention hsa-let-7a-1
(8115 sentences)


18681518 reads, 46519 reads per million, 159 experiments

     U                     uuagg   aca    c 
uggga GAGGUAGUAGGUUGUAUAGUU     guc   ccca c
||||| |||||||||||||||||||||     |||   ||||  
aucCU UUCUGUCAUCUAACAUAUCaa     uag   gggu a
     -                     -----   --a    c 

Annotation confidence High
Do you think this miRNA is real?
let-7a-3p cloned in [6] has a 1 nt 3' extension (U), which is incompatible with the genome sequence.

Genome context
chr9: 94175957-94176036 [+]
Clustered miRNAs
2 other miRNAs are < 10 kb from hsa-let-7a-1
Name Accession Chromosome Start End Strand Confidence

Disease association
hsa-let-7a-1 is associated with one or more human diseases in the Human microRNA Disease Database
Disease Description Category PubMed ID

Database links

Mature hsa-let-7a-5p

Accession MIMAT0000062
Description Homo sapiens hsa-let-7a-5p mature miRNA
Evidence experimental
cloned [1-3,5-8], Northern [1], Illumina [9]
Database links
Predicted targets

Mature hsa-let-7a-3p

Accession MIMAT0004481
Description Homo sapiens hsa-let-7a-3p mature miRNA
Evidence experimental
cloned [6]
Database links
Predicted targets


  1. PubMed ID: 11679670
    Identification of novel genes coding for small expressed RNAs
    "Lagos-Quintana M, Rauhut R, Lendeckel W, Tuschl T"
    "Science (2001) 294:853-858

  2. PubMed ID: 15183728
    Human embryonic stem cells express a unique set of microRNAs
    "Suh MR, Lee Y, Kim JY, Kim SK, Moon SH, Lee JY, Cha KY, Chung HM, Yoon HS, Moon SY, Kim VN, Kim KS"
    "Dev Biol (2004) 270:488-498

  3. PubMed ID: 12554860
    Numerous microRNPs in neuronal cells containing novel microRNAs
    "Dostie J, Mourelatos Z, Yang M, Sharma A, Dreyfuss G"
    "RNA (2003) 9:180-186

  4. PubMed ID: 14573789
    Reduced accumulation of specific microRNAs in colorectal neoplasia
    "Michael MZ, O' Connor SM, van Holst Pellekaan NG, Young GP, James RJ"
    "Mol Cancer Res (2003) 1:882-891

  5. PubMed ID: 15325244
    Altered expression profiles of microRNAs during TPA-induced differentiation of HL-60 cells
    "Kasashima K, Nakamura Y, Kozu T"
    "Biochem Biophys Res Commun (2004) 322:403-410

  6. PubMed ID: 17604727
    A mammalian microRNA expression atlas based on small RNA library sequencing
    "Landgraf P, Rusu M, Sheridan R, Sewer A, Iovino N, Aravin A, Pfeffer S, Rice A, Kamphorst AO, Landthaler M, Lin C, Socci ND, Hermida L, Fulci V, Chiaretti S, Foa R, Schliwka J, Fuchs U, Novosel A, Muller RU, Schermer B, Bissels U, Inman J, Phan Q, Chien M"
    "Cell (2007) 129:1401-1414

  7. PubMed ID: 17616659
    Patterns of known and novel small RNAs in human cervical cancer
    "Lui WO, Pourmand N, Patterson BK, Fire A"
    "Cancer Res (2007) 67:6031-6043

  8. PubMed ID: 17989717
    Small RNAs analysis in CLL reveals a deregulation of miRNA expression and novel miRNA candidates of putative relevance in CLL pathogenesis
    "Marton S, Garcia MR, Robello C, Persson H, Trajtenberg F, Pritsch O, Rovira C, Naya H, Dighiero G, Cayota A"
    "Leukemia (2008) 22:330-338

  9. PubMed ID: 20158877
    Analysis of deep sequencing microRNA expression profile from human embryonic stem cells derived mesenchymal stem cells reveals possible role of let-7 microRNA family in downstream targeting of hepatic nuclear factor 4 alpha
    Koh W, Sheng CT, Tan B, Lee QY, Kuznetsov V, Kiang LS, Tanavde V
    BMC Genomics (2010) 11:S6