Вы можете использовать следующий подход для выполнения Pivot в MySQL:
mysql> create table tabx_1(sample_name varchar(200),gene_name varchar(200),expression_value float);
Query OK, 0 rows affected (0.46 sec)
mysql> insert into tabx_1 values
-> ('Father 1','A1BG','1.53462'),
-> ('Q83X 1','A1BG','1.29403'),
-> ('Rescue 1','A1BG','1.81678'),
-> ('Father 2','A1BG','1.56481'),
-> ('Q83X 2','A1BG','0.924723'),
-> ('Rescue 2','A1BG','1.70408'),
-> ('Father 1','A1BG-AS1','1.96224'),
-> ('O83X 1','A1BG-AS1','1.92807'),
-> ('Rescue 1','A1BG-AS1','2.0421'),
-> ('Father 2','A1BG-AS1','1.61606');
Query OK, 10 rows affected (0.08 sec)
Records: 10 Duplicates: 0 Warnings: 0
mysql>
mysql> select gene_name,
-> sum(case sample_name when 'Father 1' then expression_value end) Father_1,
-> sum(case sample_name when 'Father 2' then expression_value end) Father_2,
-> sum(case sample_name when 'Q83X 1' then expression_value end) Q83X_1,
-> sum(case sample_name when 'Q83X 2' then expression_value end) Q83X_2,
-> sum(case sample_name when 'Rescue 1' then expression_value end) Rescue_1,
-> sum(case sample_name when 'Rescue 2' then expression_value end) Rescue_2
-> from tabx_1
-> group by gene_name;
+-----------+--------------------+--------------------+-------------------+--------------------+--------------------+--------------------+
| gene_name | Father_1 | Father_2 | Q83X_1 | Q83X_2 | Rescue_1 | Rescue_2 |
+-----------+--------------------+--------------------+-------------------+--------------------+--------------------+--------------------+
| A1BG | 1.5346200466156006 | 1.564810037612915 | 1.294029951095581 | 0.9247230291366577 | 1.8167799711227417 | 1.7040799856185913 |
| A1BG-AS1 | 1.9622399806976318 | 1.6160600185394287 | NULL | NULL | 2.042099952697754 | NULL |
+-----------+--------------------+--------------------+-------------------+--------------------+--------------------+--------------------+
2 rows in set (0.00 sec)