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Significant Agreements - Additional Information (Details) - USD ($)			1 Months Ended			3 Months Ended				9 Months Ended		12 Months Ended
	Jun. 18, 2021	Jun. 07, 2021	Apr. 30, 2021	Jan. 31, 2021	Dec. 31, 2020	Sep. 30, 2021	Jun. 30, 2021	Mar. 31, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020	Dec. 31, 2020	May 07, 2021
Research And Development Arrangement Contract To Perform For Others [Line Items]
Common stock, shares, issued					10,279,102	58,079,002				58,079,002		10,279,102
Research and development						$ 8,683,000			$ 2,310,000	$ 26,727,000	$ 2,733,000
General and administrative						5,919,000			$ 1,454,000	14,776,000	$ 2,444,000
Share-based compensation arrangement exercised									236,660		236,660
Common Stock
Research And Development Arrangement Contract To Perform For Others [Line Items]
Share-based compensation arrangement exercised								918,825	236,660
Stanford Exclusive License Agreement
Research And Development Arrangement Contract To Perform For Others [Line Items]
Upfront license fees received					$ 50,000
Common stock, shares, issued					600,000							600,000	640,861
Common stock additional paid in capital					$ 2,800,000							$ 2,800,000
Purchase of shares in private financings percentage					10.00%
Shares repurchased	624,845
Research and development												2,800,000
General and administrative												200,000
First commercial sale												50,000
Subsequent year commercial sale												200,000
Maximum future development and regulatory milestones payments										5,300,000
Sale-based milestones payments										7,500,000
Milestone payments										$ 0		0
Stanford Exclusive License Agreement \| First Year
Research And Development Arrangement Contract To Perform For Others [Line Items]
Annual maintenance fees												5,000
Stanford Exclusive License Agreement \| Second Year
Research And Development Arrangement Contract To Perform For Others [Line Items]
Annual maintenance fees												10,000
Stanford Exclusive License Agreement \| Third Year
Research And Development Arrangement Contract To Perform For Others [Line Items]
Annual maintenance fees												10,000
Stanford Exclusive License Agreement \| Fourth Year
Research And Development Arrangement Contract To Perform For Others [Line Items]
Annual maintenance fees												25,000
Stanford Exclusive License Agreement \| Fifth Year
Research And Development Arrangement Contract To Perform For Others [Line Items]
Annual maintenance fees												25,000
Stanford Exclusive License Agreement \| Sixth Year
Research And Development Arrangement Contract To Perform For Others [Line Items]
Annual maintenance fees												$ 25,000
License Agreement with Stanford \| Common Stock
Research And Development Arrangement Contract To Perform For Others [Line Items]
Shares repurchased	624,845						624,845
First Option Agreement
Research And Development Arrangement Contract To Perform For Others [Line Items]
Common stock, shares, issued				132,137
License execution fee				$ 10,000
Option agreement expiration term				18 months
Share-based compensation arrangement exercised										0
Second Option Agreement
Research And Development Arrangement Contract To Perform For Others [Line Items]
Share-based compensation arrangement exercised										0
Options fee			$ 30,000
LCGM Service Agreement
Research And Development Arrangement Contract To Perform For Others [Line Items]
Research and development						700,000				$ 1,700,000
Annual fee payable						2,800,000				2,800,000
IDT License Agreement
Research And Development Arrangement Contract To Perform For Others [Line Items]
Research and development						0.0				3,000,000.0
Milestone payments						0				0
Exercise fee		$ 500,000
Upfront payment		3,000,000.0
Milestones probable						$ 0				0
IDT License Agreement \| Research and Development Expenses
Research And Development Arrangement Contract To Perform For Others [Line Items]
Total consideration										$ 3,000,000.0
IDT License Agreement \| Maximum
Research And Development Arrangement Contract To Perform For Others [Line Items]
Upfront payment		5,300,000
IDT License Agreement \| Beta Thalassemia and Lysosomal Storage Disorders Fields
Research And Development Arrangement Contract To Perform For Others [Line Items]
Exercise fee		1,000,000.0
Upfront payment		$ 8,800,000